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A ' ' < 2 = wl wre wee eee ee ws Het ese ewe Ba sod es ¥ DN See ree Tibial mete he revuy! te wou. “OL wth u puttony yn Te aS ‘y | PT ETTD UT ae ote, n Pi | i me, Layee eral Ge eee epee cent es serie vet ete w b Lorie ea . 1 ad UA AL whe, er — aa nN Ul Ss ld UWwcen trees, dttaws { a Ney Oy: Vv eye rer uy 400 9 Rey eee ade. Sod dante w Ftd Pht he LAL i] Banliee “eo, v “es erie mn stig hs PUPP ire van at PR vio Mi oa Pith! wy : AY ; a : ae ‘ Pa ny ee an : a ay : : i UNIT on is i Tah an ysl neh riy ie 1 os are o > it , Aye Pin an ¥ a B Phd ral : : aay 4 i i} 1 thas a ‘Au an Au oe 7 ; : ae 7 i oe (on Y ' - Ai UD 5 ay oe an - r i D4 a el) i - i ity i ee) : Na ba : uA 4 ; a ih a oe vy ae Teall 7 5 OE aha ee f Dat Cur | “ (ores vi 6 UNIVERSITY OF CALIFORNIA PUBLICATIONS \ 4 aes } \ | SY \\ I Gy Lae BULLETIN OF THE DEPARTMENT OF GEOLOGY ANDREW C. LAWSON JOHN C. MERRIAM EDITORS : (295 E22 £ VOLUME VI WITH 43 PLATES BERKELEY UNIVERSITY OF CALIFORNIA PRESS : oneOhon f CS yf O36; 1910-1911 CONTENTS PAGE . The Condor-like Vultures of Rancho La Brea, by Loye Ilolmes DANG Y= ee a DP ee eo . The Tertiary Mammal Beds of Virgin Valley and Thousand Creek in Northwestern Nevada: Part I, Geologie History, Dy ohm (Clie ryt yin. Seso-cccecs sc-ceceeceteecenecncaceeoncenseoesees eee teeeos No. 3. The Geology of the Sargent Oil Field, by William F. Jones .... No. 4. Additions to the Avifauna of the Pleistocene Deposits at Fossil Lake, Oregon, by Loye Holmes Miller ........................ No. 5. The Geomorphogeny of the Sierra Nevada Northeast of Lake Tahoe, by John A. Reid ..2.............0..-. Soe errata eee No. 6. Note on a Gigantic Bear from the Pleistocene of Rancho La Breas by John Cs, Meni sym: oo eee cece eee No. 7. A Collection of Mammalian Remains from Tertiary Beds on the Mohave Desert, by John C. Merriam ................2...2002.----- No. 8. The Stratigraphie and Faunal Relations of the Martinez For- mation to the Chico and Tejon North of Mount Diablo, by RO ls DUCK OTS OM gece conse sacs rocks oo cectee eeceens osteo te cee eee eens eeeeeeeee tee No. 9. Neocolemanite, a Variety of Colemanite, and Howlite, from Lang, Los Angeles County, California, by Arthur 8. Eakle.... No.10. A New Antelope from the Pleistocene of Rancho La Brea, by ATER Ges lee Be Ea eae cg Se eT A No. 11. The Tertiary Mammal Beds of Virgin Valley and Thousand Creek in Northwestern Nevada: Part II, Vertebrate Fauna, Po Vedio hn sO sys Mie rr ry es esscecs cs ostcecesaees c-ceces snctesees . IN . dente ie $ ; NORTHWESTERN NEVADA) = eae Ck BN ; ee _ JOHN C. MERRIAM © 3 PART IL—GEOLOGIC HISTORY ae, eee « « jqvs0t oy BERKELEY - THE UNIVERSITY PRESS cnreaae OF ‘CALIFORNIA PUBL Notr.—The University of California Poblications?s are offered in eations of learned societies and institutions, universities and libraries. — mp all the publications of the University will be sent upon request. For sample publications and other information, address the Manager of the Univ ¥ California, U. S. A. All matter sent in exchange should be addressed Department, Ces Library, Berkeley, California, U. S. A. a Our HARRASSOWITZ R. FRIEDLAENDER ¢ & Sonn LEIPZIG BERLIN ¥ Agent for the series in’American Arch- Agent for the series in America’ 1 Axe) aeology and Ethnology, Classical Philology, aeology and Ethnology, Botany, piak Vs Edueation, Modern Philology, Philosophy, Mathematics, Pathology, = Phy. jv ioe. Psychology. Zoology, and Memoirs. | Geology.—Awnprew C. Lawson and Joun C. Merriam, Editors. Price per volume. $2550, Volumes I (pp. 428), II (pp. 450), ILI (pp. 475), IV (pp. 462), V (pp. a completed. Volume VI (in progress). Cited as Uniy. Calif. Publ. Bull. Dept. Geol. VOLUME 1. Beer 1. The Geology of Carmelo Bay, by Andrew C. Lawson, with chemical analyses ana cooperation in the field, by Juan de la C. Posada... 2.0... ..cccccceecccceceeeteeeeeeeeeeeeeee- Bde 2. The Soda-Rhyolite North of Berkeley, by Charles Palache........00----ccc0--0------------ gen i 3. The Eruptive Rocks of Point Bonita, by F. Leslie Ransome........-.0--.--.----- Ba, 44 4. The Post-Pliocene Diastrophism of the Coast of Southern California, by Andrew iv Toawison fr sek sel Ts aa ee et nr 40¢ 5. The Lherzolite-Serpentine and Associated Rocks of the Potrero, San Francisco, ia Charles Palache. 6. On a Rock, from the Vicinity of Berkeley, containing a New Soda Amphibole, ly Charles Palache. NOs. fonand!6 am one cover 22a ee 7. The Geology of Angel Island, by F. Leslie Ransome, with a Note on the Radiolarit.« Chert from Angel Island and from Buri-buri Ridge, San Mateo County, Californ*,,, by. George Jennings: Hinde: +205 32 ee ¢ oe 8. The Geomorphogeny of the Coast of Northern California, by Andrew C. Lawson. 10% 9. On Analeite Diabase from San Louis Obispo County, Galteertec by Harold MG Mairbamles ie") 0020) boc CES Ee ian A ely See 7a 10. On Lawsonite, a New Rock-forming Mineral from the Tiburon Peninsula, Maz County, California, Joy. H), eslie Riamsomn eos ae. pe sae eee ae peste 11. Critical Periods in the History of the Earth, by Joseph LeConte.....---.--c0c0------ ; 12. On Milignite, a Family of Basic, Plutonic, Orthoclase Rocks, Rich in Alkalies and . Lime, Intrusive in the Coutchiching ‘Schists of Poohbah Lake, by Andrew CoabaiwSo mos ios nl TR No ER ee 13. Sigmogomphius LeContei, a New Castoroid Rodent, from the Pliocene, near , Berkeley, by. John .C. Merriam: 2.22... 25-year 14. The Great Valley of California, a Criticism of the Theory of Isostasy, by F. Leslie Ransome; -2.2..- gis A ee ee ee : VOLUME 2. 1. The Geology of Point Sal, by Harold W. PWairbanks 25. 1202 225 = See eens 2. Of Some Pliocene Ostracoda from near Berkeley, by Frederick Chapman............. 3. Note on Two Tertiary Faunas from the Rocks of the Southern Coast of Vaneoutver Island by gv... Go; Memriaym 5s eo ae ee ec eee ee eee Le Sd eee : 4. The Distribution of the Neocene Sea-urchins of Middle California, and Its Bears on the Classification of the Neocene Formations, by John C, Merriam é 5. The Geology of Point Reyes Peninsula, by F. M. Anderson... 6. Some Aspects of Erosion in Relation to the Theory of the Peneplain, by w. S: Maneter “Smiith: 2... ce hoe Se Ses oe 7. A Topographic Study of the Islands of Southern California, by W. S. Tangier Smith 8. The Geology of the Central Portion of the Isthmus of Panama, by Oscar H. Hershe. 9. A Contribution to the Geology of the John Day Basin, by John C. Merriam. 10. Mineralogical Notes, by Arthur S. Baklecee ae ee ee ie ee 11. Contributions to the Mineralogy of California, by Walter ©. Blasi). 12. The Berkeley Hills. A Detail of Coast Range Geology, by Andrew C. Lawson a @harles;*Palache :<.2.A.5 2 2 Se ee ee UNIVERSITY OF CALIFORNIA PUBLICATIONS BULLETIN OF THE DEPARTMENT OF GEOLOGY Vol. 6, No. 2, pp. 21-53, Pls. 1-12 Issued November 30, 1910 TERTIARY MAMMAL BEDS OF VIRGIN VALLEY AND THOUSAND CREEK IN NORTHWESTERN NEVADA BY JOHN C. MERRIAM. PART I—GEOLOGIC HISTORY. CONTENTS. PAGE MVGTVG RO CUULC GL OME Wee sets sse ce ck ed 2 aete fe oes ey edeal s, Segue eb aeyied sxevs teases, deevss Atevdluy ei eceisti 22 PAICKM OWE COIN CICS! eeccseecee ee cecede see eaceeceeeee bec =epeeeeece se SO ee ee eee ee ee ee 23 General physical features of the region —..........2...0.0002. eee eee 24 (Cieolloyeni@ aspen UITSAS) Coe INVES aeFe gM ae ese ee 25 JEXBKSY OMG), TRAVERS) XSL OY 0 ge re Ra are rp 26 JE abayes DGS SHY ARH a ee em eg yee Se eee eee Leer ee 29 BVA FMM Vic Var SCCULOM sofa, cece ncencee 2s ese conde ses eceete see sas ctcelecedestens 30 COPS AMORA AEP U 0) DU eo pe eee 31 pValirs ovine Valli ye ES © CLS esses oe sate co ece cece see oe etes cadeccetseecdeecs candi ce-ccece secede. ce sageuses 33 MiesaBasalt e620 2 ef eae oe Pass Satta 2ey Foes eons 36 History subsequent to outpouring of Mesa Basalt ...........0..2..........- 38 Mn Onsamdle Greek WB CCS: ee seee ees p2 esc ec ence econ ctenaes soon eesewncceqaenosesneesesbecteeesieeacece 43 JeaLalogl an, Tear edee: (OPW ANON aY: Ceo: e OO }S|UD SSS ee gegen Pr ee ee 51 Physical conditions obtaining during deposition of Virgin Valley and A RYIQGXUISEE WAV bk Ci geTeN GU 120 Ee a ee 51 Summary of principal events in the geologic history of the Virgin BV cUlll ery mse Od O neem ea ease o Pec soot vated tena ct ee oes we seed aati, eeke eat e 5 ~ tb t University of California Publications. | GEOLOGY INTRODUCTION. The Tertiary fossil beds of northwestern Nevada were first brought to the writer’s attention in 1905 through Mr. Robert L. Fulton, who kindly permitted the examination of several frag- ments of bones and teeth obtained in Virgin Valley by Mr. Allan C. Bragg, and given by him to Mr. Fulton. In the attempt to obtain information regarding the geology of the region, the late John A. Reid, then Professor at the University of Nevada, assisted in every possible way. In June, 1906, the writer, in company with Felix T. Smith, a student at the University of California, made a reconnaissance of the Virgin Valley region and obtained a small collection of fossils. In a brief statement of the results of this study pub- lished by the writer’ the formation in Virgin Valley was desig- nated as the Virgin Valley Beds. It was considered as Miocene, with the suggestion that the upper part of the series was prob- ably not older than the Maseall stage of the John Day region. In a discussion of some of the ungulate material collected largely in the older beds at Virgin Valley by Merriam and Smith in 1906, J. W. Gidley? expressed the opinion that all of the specimens in the collection examined represented middle or lower Miocene, and that they might be somewhat older than the Maseall. In the summer of 1909, Miss Annie M. Alexander very kindly offered to organize and finance an expedition to Virgin Valley to carry on the work which had been suggested by the reconnais- sance in 1906. The party organized by Miss Alexander spent - three months in the field, and after working over the exposures at Virgin Valley and Thousand Creek, the exploration was extended to several localities near Soldier Meadows to the south of Virgin Valley, where a number of new exposures of mammal beds were discovered. The available information relating to the mammal beds of the Virgin Valley and Thousand Creek region is presented in 1 Science, n. s., 26, pp. 380-382. Sept. 20, 1907. 2 Univ. Calif. Publ. Bull. Dept. Geol., 5, p. 242. 1908. BULL, DEPT. GEOL. UNIV. CAL. VOIES 6) Ii. ELLENSBURG FORMATION — JOHN] DAY BASIN _ACROOKED RIVER PAYETTE aN NEWADA fi | Outline map showing situation of the Tertiary mammal-bearing beds of northwestern Nevada. [ g y g Vou.6] Merriam: Virgin Valley and Thousand Creek. 23 two parts issued separately. The first part includes a general description of the region, a history of investigation carried on there, and a discussion of the geologic history. The second part contains a discussion of the extinct mammalian faunas of these beds, with a consideration of all the accumulated information contributing to an understanding of the age of these faunas and of the formations in which they are found. ACKNOWLEDGMENTS. In presenting the following report on the work of the 1909 expedition in northwestern Nevada, the writer wishes to express his indebtedness to Miss Annie M. Alexander for making the expedition possible through its financial support, and for the personal interest with which the field work was carried on under difficult conditions. The writer is also much indebted to Miss Louise Kellogg, who joined in the field work with Miss Alex- ander and materially contributed to the success of the party. During the field operations E. L. Furlong devoted special attention to the occurrence and distribution of the mammalian remains obtained, and to the nature of the mammal beds. Mr. Furlong also had immediate charge of the fossil collections. A. J. Heindl brought together a representative collection of rock specimens illustrating the principal lithological phases of the formations occurring in the region investigated, and made a series of notes on their occurrence and structure. In carrying out the work of the expedition the Pacifie Live Stock Company, through all of its representatives with whom the members of the party came in contact, most generously assisted in every way possible, and contributed greatly to the efficiency of the expedition. Particularly in connection with the work in the field, mention should be made of assistance by Mr. F. M. Payne, who was very helpful to the party. The writer is also indebted to T. H. MeGhee and Edward McGhee of Virgin Valley for information regarding the occur- rence of fossil remains. It should be stated that Edward McGhee is, so far as known to the writer, the first person to discover fossil bones in Virgin Valley. On the reconnaissance trip made 24 University of California Publications. | GEOLOGY by the writer in 1906 T. H. McGhee very kindly indicated to us the situation of some of the most important fossil localities in the region. GENERAL PHYSICAL FEATURES OF THE REGION. The region in which the mammal-bearing beds of Virgin Valley and Thousand Creek are situated les between two fairly defined areas of quite different topographic nature. To the east and south there is a suecession of sharply defined mountain ‘anges with a general north and south trend, between which are broad and remarkably flat valleys. The Pine Forest and Pueblo ranges, which form the eastern border of the region in which the principal field work was carried on, rise to a height of over 9000 feet. The broad valleys have an elevation of about 4000 feet. As is so frequently shown in the Basin region, the develop- ment of the mountain chains to the east of Virgin Valley is evidently due in a large part to faulting. The remarkably even filling of the valleys was accomplished in part by alluvial wash, and partly by accumulation in lakes. A series of terraces dis- tinctly shown bordering the flats near Sodhouse Point and near Mason’s Crossing, in the valleys immediately to the east of Pine Forest Range, represents the shore-line of a body of water which must have covered a large part of the valley floor in this region during some portion of Pleistocene time. Associated with the terraces are remnants of marginal deposits containing a fresh-water mollusean fauna. Along certain levels, the marginal deposits of the ancient lake show an extraordinarily heavy cal- careous deposit. According to Russell’ this region was occupied by the northern extension of Lake Lahontan, and the terrace deposits to which reference has just been made were evidently formed during that period of deposition. In the region to the west of Virgin Valley the country is largely lava-covered, and is evidently a southward extension of the great lava plateau in the Oregon region to the north. The valleys here are either broad and comparatively shallow depres- 3 Russell, I. C., Lake Lahontan, Monog. U. 8. Geol. Surv. no. 11. 1885. Bed EL vga SON jc 4h wor) venetian nsec sh cr se an erin Fh Ya sa sat sre afew eh fe oes ir arent vegan ati Lease fee AURA Fee a i ~ aire aise Arie orrentiypvirS Lachyny ay 298 OT alge y Gh) \ 4 “A )\ dM Z Bi / ji i : , N Z : MESA BASALT A Gg a \ Af LIENS i ; eal at | N 0) ye es poased ro! aD Al SY | . NUE eS Lh Ee wnN AU Cha. ence vaya!) REC ys Wo decks waite’ i My vat fe pe SARA Ea ean SE om TPN LR AN AN os JRE CIO ANTM eterno gente ar tenrsoyct ar, ardent ng epee Wqnba Vou.6] Merriam: Virgin Valley and Thousand Creek. 25 sions, due to crustal movements of less magnitude than those which produced the deep, broad valleys to the east; or they are comparatively narrow canons due to erosion. The general level of this region is much higher than that of the broad valleys to the east. The region under consideration may be classified, as a whole, as semi-arid, excepting some of the highest zones of the larger mountain masses. Over the greater part of the area sage-brush is the dominant type of vegetation. Trees are almost entirely absent, excepting scattered junipers on the hills, a few alders and willows along the streams, and a few pines in the highest zone. Notwithstanding the generally arid nature of the country, there is sufficient grass, and other vegetation which may serve as food for herbivorous animals, to support a large mammalhan population. In comparatively recent time the ungulates have been quite abundantly represented by prong-horn antelope, deer, and mountain sheep. At the present day the carnivores are num- erously represented by coyotes, wild-cats, and badgers, and an abundant rodent population includes many genera and _ species. The fauna as a whole is surprisingly rich in variety of forms and number of individuals. GEOLOGIC FEATURES OF THE REGION. The geologic features of the region visited by the expedition present a most attractive study. A considerable number of well-defined formations are represented and numerous in- structive sections are exposed by extensive fault-scarps and deeply eroded canons. The district immediately surrounding the field examined apparently shows a range of geological systems extending from Palaeozoic to Quaternary. As the primary object of the expedition was to obtain a representation of the mammahan fauna of the sedimentary formations in the Virgin Valley region, the acquisition of palaeontological material was the occupation of first importance. Investigation of the formations represented has therefore of necessity been confined almost exclusively to the fossil-bearing beds with those adjacent to them, and may not be considered as more than a reconnaissance. 26 University of California Publications. | GEOLOGY In the region investigated, five fairly distinct geologic sections were examined; viz., those of Pueblo Range, Pine Forest Range, Virgin Valley, Thousand Creek, and High Rock Canon. For the purpose of description these sections are dis- cussed separately. PUEBLO RANGE SECTION. Previous to the brief note published by the writer in 1907* the only reference to the geology of the region near Virgin Valley known to have been published is that of Blake®, in 1875, on the Pueblo Mountains, extending southward along the east side of the Thousand Creek region (pl. 2). Blake described a section of the beds across the Pueblo Range which corresponds very closely in its upper portion with a profile of the southern extremity of this range made by A. J. Heindl, and confirmed by the independent observations of EK. L. Furlong and the writer in passing through this region. According to Blake, the lowest formation is a ‘‘porphyry’’ which is overlain on the east side by ‘‘metamorphiec rocks, prin- cipally micaceous and talcose schists with some metamorphic limestones. These have a dip of about 78° E. with a strike generally North 16° E. They appear to have been thrown up by an eruption of porphyry, which now forms the crest of the ridge.’’ The western portion of the section is formed by a ridge which overlaps the eastern ridge both at its north and south ends. The western ridge was described as ‘‘composed entirely of voleanie rocks, arranged in regular strata, with a dip of 20° to the west. They form perfectly conformable layers, and extend from its base to the summit of the ridge, a height of more than 1200 feet, 6,000 feet above the level of the sea. The beds are composed of many varieties of voleanic rock.’’? The section of the western ridge consisted mainly of basalts below, with trachytie rocks at the top. At the southern end of the ridge Blake observed strata considered as of aqueous origin. ‘‘ They were laying perfeetly conformable on volcanic rocks and were covered in by a layer of gray trachyte also perfectly conformable 4 Science, n. s., 26, p. 380. Sept. 20, 1907. 5 Blake, J., Proe. Calif. Acad. Sci., 5, pp. 210-214. 1875. Vout. 6] = Merriam: Virgin Valley and Thousand Creck. 27 with these aqueous beds. The beds were about 200 feet thick, consisting of strata of white and red argillaceous rocks, rolled conglomerate, and were all evidently formed from debris of voleanie rocks, the conglomerate being made up principally of rolled pumice.”’ Blake pointed out particularly that the succession of igneous rocks, in which basalts occurred below trachytes, did not agree with Richthofen’s system. He also expressed the view that ‘‘the geological formation of this range will be found to be repeated in the vast outflows of voleanie rocks that cover so large a portion of Eastern Oregon, extending north beyond the Columbia River.”’ No definite evidence of the age of any of the formations was given by Blake, though he suggested that the erupted rocks were early Miocene, and that the older rocks of the eastern ridge were probably Triassic. Waring ® in his account of the Geology and Water Resources of the Harney Basin Region, Oregon, refers to the work of Blake and speaks of the Pueblo Mountains as ‘‘composed of rocks that belong to an older series than do the lavas to the north. These mountains were only cursorily examined, but from float specimens that were collected along the eastern base of the range they appear to be made up of andesitic porphyries, micaceous schists, and granitic rocks, which have been more or less extensively affected by mineralizing agents.’ In Waring’s paper on the Harney Lake region, the geology of an extensive area to the north of Virgin Valley and Thousand Creek has been outlined. Unfortunately the geologic mapping was not earried to the southern end of the Harney Valley sheet on Waring’s map, but was discontinued about twenty miles north of the Oregon line. The northernmost point reached by the University of California expedition in 1909 is situated near the southern border of Oregon. The section at the southern end of the Pueblo Range was examined in detail by Heindl in the ridge opposite Mud Lakes. At this point a thickness of about eleven hundred feet in the 6 Waring, Gerald A., U. S. Geol. Surv., Water-Supply Paper, 231, p. 18. 1909. 28 University of California Publications. | GEOLOGY upper portion of the series is exposed by a sharp fault along the west side of the lake. The beds here dip at an angle of about twenty degrees to the north of west. The section as obtained by Heindl is shown in figure 1. RHYOLITE RHYOLITIC TUFF OLIVINE, BASALT BASALT (SOLID) BASALT (VESICULAR) Fig. 1.—Cliff section showing a portion of the Pueblo Range Series immediately west of Mud Lakes. As nearly as can be determined the sequence here agrees with that observed by Blake’. To the west of this extension of the range there is a con- siderable thickness of ashes and tuffs resting upon the beds exposed at Mud Lakes. Above these ash beds are still later eruptives which Heindl believes to be rhyolite. This portion of the section presumably corresponds to the upper portion of Blake’s section showing beds considered to be of aqueous origin. According to Blake the beds of supposed aqueous origin were conformable with the voleanic rocks below them, and _ were covered by a layer of gray trachyte, also conformable. The sedimentary beds consisted in part of conglomerate which was made up largely of rolled pumice. Seen from some distance to the south, the great series of the Pueblo Range eruptives and the associated beds appears as a remarkable example of evenly tilted strata, extending back toward the mountain core by regular steps as each hard stratum is passed. The whole series runs under the plain of Thousand Creek to the west with a fairly uniform dip of approx- 7 Op. cit. 1875. Vou. 6] Merriam: Virgin Valley and Thousand Creek. 29 imately twenty degrees. In all of the localities in which the mammal beds of Thousand Creek have been observed they are nearly horizontal. Though no observations have been made at their actual contact with the older formation, there would seem to be a strong angular unconformity between the two. Whether the sedimentary beds in the upper portion of the Pueblo Range section actually belong with the lavas and tufts below is not certain. They, with the lavas, appear to represent one general period of deposition. At all events they both antedate the period of deformation which preceded the deposi- tion of the Virgin Valley and Thousand Creek beds. For practical purposes it is desirable to refer to the rhyolites and basalts on the western side of the Pueblo Range, with whatever eruptives or other beds may be shown to belong in the same series, as the Pueblo Range Series, a geographic designation indicating the section first described by Blake. This section is geographically so situated that it should be possible to correlate it with other igneous series in the region of southern Oregon and northern Nevada. To this series the Canon Rhyolite bordering Virgin Valley apparently belongs, although it is not entirely certain whether it represents exactly the same horizon as the rhyolites exposed in the upper part of the section immediately to the west of Mud Lakes. g i \ sei . : Vou.6] = Merriam: Virgin Valley and Thousand Creck. 31 but are less distinctly folded than the basal rhyolites. The basalt capping is practically horizontal. Canon Rhyolite—In Virgin Valley, and also at Thousand Creek, the formation underlying the mammal beds consists of rhyolitic flows. In Virgin Valley this basal series is folded into a syncline containing the Virgin Valley Beds. The rhyo- lites are well exposed on the western side of Virgin Valley at Hard Rock Ridge near Virgin Ranch, where they are dipping gently to the northeast beneath the Virgin Valley Beds. These beds form the sharp gorge through which Virgin Creek enters the valley from the southwest. To the east, the rhyolites form Thousand Creek Ridge, which slopes gently to the southwest and drops off precipitously to the east (see pls. 3 and 4, and text fig. 2). Through this ridge the drainage of the valley escapes In a deep, narrow cafon cut by Thousand Creek. At Thousand Creek Canon the rhyolites are exposed to a thickness of not less than four hundred feet and dip gently toward the southwest, or toward the middle of Virgin Valley. At the top of the hill above Thousand Creek Canon, the uppermost beds to the south of the wagon road are practically horizontal, and judged from their position possibly represent a phase of the rhyolite laid down after the earlier portion of the formation had been eroded and deformed. From this upper phase much of the rhyolite occurring as pebbles and boulders in the rhyolitic gravels apparently interbedded with the Virgin Valley Beds (see p. 41), seems to have been derived. The rhyolite flows are accompanied by tuffs, which are exceedingly coarse in places, the fragments of pumice in them being in many cases several inches in diameter. The precipitous slope on the east side of the rhyolitie out- crop at Thousand Creek Canon is a fault-scrap, the base of which is covered on the east side by the mammal beds of Thousand Creek. On the eastern side of the Thousand Creek basin the same mammal beds rest upon the rhyolites forming the upper portion of the eruptive series on the northwestern flank of the Pueblo Range. The rhyolites of Thousand Creek Canon may be traced around the borders of Virgin Valley to the northwest along the 32 University of California Publications. | GEOLCGY valley of Beet Creek, and seen from a distance they appear to form the sharp gorge at the upper end of Beet Creek (fig. 3, p. 37). The rhyolites evidently extend south from Thousand Creek to the valley of Gridley Lake, where Heindl found them exposed on the west side of the valley by a fault running northeast and southwest, in a line nearly continuous with that of the fault west of Mud Lakes to the north. The western flank of Pine Forest Range just to the east of Gridley Lake valley seemed to Heindl to consist of an eruptive series similar to that exposed in the fault-scarp on the west side of the valley. An outlying mass of rhyolite is also seen in a prominent hill known as Antelope Butte, which rises above the lava-covered mesa south of Virgin Valley (see fig. 4, p. 41). The rhyolites in these several regions are quite similar petrographically, they are always below the mammal-bearing formations, they have experienced about an equal amount of deformation, and there is evidence indicating that they belong to the series of eruptives flanking the western side of the Pine Forest Range; so that they may all be considered as represent- ing approximately the same horizon. From their occurrence in gorges around the borders of Virgin Valley, these lavas may be known as the Canon Rhyohte. They are presumably only a portion of the extensive series for which the geographic appel- lation of Pueblo Range Series is used. As was shown by Blake* the rhyolites of the Pueblo Range are only the uppermost portion of a thick series composed. largely of basalts. In his mapping of the formations of southeastern Oregon, Waring’ has recently shown that the principal series of lavas occurring over this region consists largely of basalts followed in many instances by rhyolites. The rhyolites of the Virgin Valley region are presumably only the upper portion of this extensive formation. As has been stated by both Blake and Waring, there is reason to believe that this series of erup- tives is to be correlated with the great lava beds reaching over a very wide extent of territory in the Columbia River region. 8 Op. cit., p. 214. 1875. 9 Op. cit. 1909. VoLt.6] = Merriam: Virgin Valley and Thousand Creek. 33 As extensive lava formations both older and younger than the Columbia Lava are well known in the great Columbia River area immediately to the north, it is desirable that the eruptive series of southern Oregon should be carefully compared with those of several typical sections where the age and relationships of the lavas have been determined. From the point of view of general geology it is very desirable that an attempt be made to connect the area mapped in southern Oregon with the section of the John Day region, which is the most satisfactory series of formations for correlation purposes that has yet been observed in this region. With our present knowledge of the eruptive formations of southern Oregon, there is reason for considering the principal lava series, of which the Pueblo Range Series seems to be repre- sentative, as presumably, though not certainly, the correlative of the definite horizon of eruptives situated between the John Day and Maseall formations on the John Day River, at Picture Gorge, near Dayville, Oregon. To this phase of the igneous succession the name Columbia Lava has been definitely lmited by the writer’, as it seemed desirable not to discard entirely the name so appropriately suggested by Russell"? for the great lava flows of the Columbia River region". Virgin Valley Beds.—Resting upon the Canon Rhyolte in Virgin Valley is a thick sedimentary series, consisting largely of voleanic ash and tuff, which has been designated as the Virgin Valley Beds’* (see pl. 5; and text fig. 2, p. 30). It is from this formation that the Tertiary mammalhan fauna of Virgin Valley is obtained. The Virgin Valley Beds have been protected by the over- lying Mesa Basalt, which now forms extensive table lands on each side of the valley; and in the escarpments bordering the mesas exceptionally good sections are exposed. Although a con- siderable fauna has been obtained from these beds, vertebrate remains are nowhere abundant in them, and the collections available represent much painstaking effort. 10 Univ. Calif. Publ. Bull. Dept. Geol., 2, p. 303. 1901. 11 Russell, I. C., U.S. Geol. Surv. Bull. no. 108, p. 20. 1893. 12 This igneous series has also been known as the Columbia River Lava. 13 Merriam, J. C., Science, n.s., 26, 1907, p. 380. ’ 34 University of California Publications. | GEOLOGY The thickness of the Virgin Valley Beds, measured from the uppermost strata to the floor of the valley, is about 1500 feet. The beds are evidently thinnest around the edge of the valley, and the bottom of the formation is not reached at the point where the measurements were made. Even taking into account a slight dip of the beds from the highest point toward the lowest level, the total thickness may be estimated at over 1500 feet. Throughout the whole extent of the valley the strata are found to vary only a few degrees from a horizontal position, excepting through landshdes. Such variation from the hori- zontal as is shown expresses a gentle syncline with the depression near the middle of the valley. This is presumably due mainly to a slight deformation which has taken place since the principal accumulation occurred. It may be due in a small part to con- formation to the form of the trough in which the beds were laid down. The Virgin Valley Beds are almost entirely made up of voleanic ash and tuff. At several horizons gravel, sand, clay, henite, and diatomaceous deposits occur, but are of much less volume than the beds of purely volcanic origin. The lowest strata recognized in the valley are ashes and tuffs dipping gently to the west along the western side of Thousand Creek Ridge (pl. 5). These strata are predominatingly white, but range in color through bright red, purple and green. This phase is overlain commonly by a series of dark red beds which have quite an extent along the stream bed in the northern part of the valley. The lowest beds of the series rest upon the irregular surface of the Canon Rhyolite. Such evidence as is available suggests unconformity between the lower Virgin Valley Beds and the Canon Rhyolite. The white ashes of the lowest portion of the section have probably accumulated quickly. The dark red horizon presum- ably represents a period of slower accumulation with extreme oxidation. The mode of accumulation of the lowest beds examined is not strongly suggested by any evidence obtained thus far, but they are not improbably aeolian. The red beds are possibly aeolian. BULL. DEPT, GEOL. UNIV. CAL. VO reGye lacs) View of Virgin Valley looking west across the valley of Virgin Creek from the foot of Thousand Creek Ridge. Basal Virgin Valley Beds in foreground. Mesa in background composed of Virgin Valley Beds capped by Mesa Basalt. Lower Virgin Valley Beds with mammal-bearing strata covered by earbonaceous shales. East side of Virgin Valley. 1 4 a . ‘ : i ‘ i ‘ P : ‘ i ee * . t - ‘ ; : a { : i hs 5 Carbonaceous shales with thin seams of lignite. Lower pl se of Virgin Valley Beds, south side of valley of Beet Creek. i ‘ r ts ; 3 ‘ “ ‘ . ey - ; . Vou.6] = Merriam: Virgin Valley and Thousand Creek. 35 The section of the formation immediately above the dark red horizon is distinguished by a brownish-yellow coloration over a considerable part of the valley. The same general horizon is apparently represented by a grayish or buff phase in many places. In that portion of the section above the red beds, at some localities in the yellow phase and at others either below or above it, there are considerable thicknesses of thinly-bedded, highly carbonaceous shales which may contain numerous lignitie layers (pls. 6 and 7). The shales are largely clay and ash, but may be diatomaceous. The lignitic seams are very numerous in some of the sections, as on the south side of the valley of Beet Creek. They have usually a thickness of only an inch or two. Prospecting for coal has been carried on in this portion of the series but no deposits of economic value have yet been dis- covered. A number of fossil leaves were obtained in the seetion on Beet Creek. It has been found very difficult to transport speci- mens owing to the friable nature of the rock, and only a few species have been obtained for study. At one locality of the middle beds in Virgin Valley opal specimens of some commercial value are found. The opals occur largely in cracks or cavities in the typical fossil-bearing beds of this horizon. The deposits of that portion of the Virgin Valley represented by the yellow beds and the carbonaceous strata were certainly in part laid down in water. The diatomaceous beds are of aqueous origin, and some of the gray clayey strata which are found to contain fish-bones in considerable numbers must also have been formed in water. The shales with numerous hegnitic seams are evidently swamp or lake deposits in a large part. That portion of the Virgin Valley Beds above the yellow and the carbonaceous phase of the formation constitutes the largest part of the series of beds exposed. It is made up almost entirely of white to buff or cream-colored ash and tuff. Some strata are almost pure, sharp-edged ash which has been but lttle worked over. In other beds, the glass is much decomposed and the material has apparently been worked over considerably. There 36 University of California Publications. [GEoLcey are in this portion of the section a number of beds of gravel and boulders which are evidently of fluviatile origin, but the impression given by this section as a whole is that it is largely of aeolian origin. This suggestion is also supported by the nature of the fossil remains in these beds, which are those of land forms. This does not preclude the possibility that some of the strata accumulated in temporary lakes. During the deposition of the Virgin Valley Beds the con- ditions of accumulation were apparently much as those at the present time in most of the large valleys of the Nevada or eastern Oregon region. The Canon Rhyolite evidently formed the rim of the valley, while the sediments laid down in it were spread out to form a broad and nearly level floor. Whether the conditions were such as to cause sedimentation in water or in air, the evenness of the stratification remained much the same. As suggested under the discussion of the later history of this region (see p. 43) there is reason for believing that a considerable thickness of rhyolitic gravels resting unconformably upon the middle beds of the Virgin Valley section in the angle between the valleys of Virgin Creek and Beet Creek (pl. 8), represents deposition within the Virgin Valley epoch. Whether this unconformity exhibited here is general throughout the Virgin Valley section, or whether it is a purely local feature is not known. If it should be found to represent a widespread condition of erosion, it would be necessary to divide the Virgin Valley section into an upper and a lower division. In this ease, the name Virgin Valley Series may be apphed to the whole eroup of beds between the Canon Rhyolite and the Mesa Basalt. The beds below the unconformity would then be known as the Lower Virgin Valley Beds, those above the unconformity the Upper Virgin Valley Beds. Mesa Basalt.—Where they are not uncovered by erosion, the Virgin Valley Beds are capped by an extensive sheet of olivine basalt of a doleritie facies. This capping forms the ‘‘rim rock’’ of the great mesas on both sides of the valley of Virgin Creek and may be known as the Mesa Basalt (see pls. 9 and 10, text fig. 2, p. 30, and text fig. 3). So far as observed, the lava sheet is not distinctly unconformable upon the underlying Middle division of Virgin Valley Beds covered unconformably by rhyolitie gravels. South side of valley of Beet Creek. f Upper Virgin Valley Beds covered by Mesa Basalt. Northwest side of valley of Virgin Creek, exposure near A of A-B line shown on plate 2. Vou. 6] = Merriam: Virgin Valley and Thousand Creek. 37 beds. The table-lands covered with this lava capping are known to extend for a distance of fifteen or twenty miles north and south. As seen from a commanding point above its level, the table-land appears to have an extent several times the length of the seetion in which the basalt capping has actually been traced, and the presumption is that this flow reaches over a territory much larger than that personally visited. The surface of the basalt cap, and of the mesas in general, is normally = _——,_— a ~ iF SA BASALT == VIRGIN VALLEY BEDS |" oer big, fA CANON RHYOLITE Fig. 3.—View of the mesa north of Beet Creek. See also plates 2 and 10. nearly level, or with only shght undulations. Several faults of considerable magnitude have developed in the mesa to the northeast of Virgin Valley in the movement of large crustal blocks in comparatively recent time. To one traveling over the mesas, the surface of the tabl: presents a most unusual spectacle. The lava is only partly covered by irregular patches of soil in which no plants larger than sagebushes have developed. The evenness of the surface and the unvarying nature of the long stretches of sagebrush and lava blocks are such as to make a judgment of distance most difficult. Above the surface of the lava there rise here and there a few prominent points (see pl. 10), as Antelope Butte (fig. 4, p. 41) situated on the mesa south of Virgin Valley. This point consists of a dome of rhyolite which projects as an island rising three hundred feet above the level surface of the basalt flow. The basalt sheet is near twenty-five feet in thickness over the region where it has been examined, and consists of several fairly distinct layers. The separate beds observed may not be persistent, and may be nothing more than local advances of a single flow. The uniformity in thickness is quite remarkable, and evidently indicates that the lava was poured out on a nearly even plain. Though the dissection of the mesas by erosion 38 University of California Publications. [GEOLOGY has exposed splendid sections of the region formerly covered by the basalt, no dikes or fissures have been observed through which this lava has come to the surface. Such sources may, however, appear in localities not yet visited. The extent of this flow appears rather remarkable when considered in relation to its thinness. It is difficult to understand how a flow could extend itself so broadly without heaping up more than is indicated in this section. Taking into consideration the thinness of the flow and the evenness of the floor upon which the Mesa Basalt was laid down, the present aspect of the table-lands surrounding Virgin Valley may be considered as closely representing the nature of the topography of this region during the latter part of the epoch of deposition of the Virgin Valley Beds. If the lava sheet were removed, the sedimentary beds below would form a nearly level plain reaching well up on the side of the range to the south. Many of the salient features of the topography which existed in early Virgin Valley time would be completely buried, while a few of the highest points would project as islands rising sharply above the surrounding ash accumulation. History Subsequent to Outpouring of Mesa Basalt.—No accumulation of sediment has been observed to rest upon the Mesa Basalt. Though such formations may possibly exist in localities that were not visited, the impression received in a general survey of the table-land region is that the basalt sheet was the last deposit laid down in the region anterior to the events that initiated the cycle of erosion during which the present valley was excavated. Movements following the outpouring of the basalt sheet are evidenced in the presence of a sharply-marked fault along the line of the scarp following the east face of Thousand Creek Ridge. The basalt cap to the north of Thousand Creek Canon is sharply cut off along the extension of the axis of the ridge, the mesa on the east side of the jog dropping a little over four hundred feet below the level of the mesa to the west. This movement is a late phase of the adjustment of crustal blocks which evidently began moving before the deposition of the Virgin Valley Beds. It is not improbable that a small amount BULL, DEPT. GEOL. ‘UNIV. CAL. VOL Tiew of mesa north of valley of Beet Creek. Table land capped by Mesa Basalt resting upon Virgin Valley Beds. 9 Canon Rhyolite underlying Virgin Valley Beds in middle distance to left of picture. See also text-figure 3. Vou.6] = Merriam: Virgin Valley and Thousand Creek. 39 of movement occurred along this line during Virgin Valley time. The level of the region to the west of the fault-line must have been somewhat higher than that of the country to the east after the basalt outflow in order to permit the establishment of the present drainage system, which flows toward the east across Thousand Creek Ridge. The drainage system of Virgin Valley as it now appears is a very interesting feature of the region, as it pursues its course apparently without respect to very prominent barriers (see pl. 2). To the north, west, and east of the valley the streams eut narrow canons through very hard ridges of the older rhyolitic rocks; while the stream-beds in the valley proper are broad, and in some eases widen out into marshy belts. The small stream of Thousand Creek, formed by the union of Virgin and Beet creeks, leaves the broad, open valley to cut straight into the hard rhyolite of Thousand Creek Ridge, through which it passes In a very narrow canon (pls. 3 and 4). It is evident that the barriers crossed by the present drainage were passed in the process of cutting through the Virgin Valley Beds and into the buried ridges of the older formation. The general progress of canon cutting may have been retarded considerably at times by the nature of the vupposing barriers and movements along the fault-line crossing the stream at the mouth of Thousand Creek Canon possibly retarded it still farther. During the process of excavation of Virgin Valley there appear to have been several resting stages of which some record is left in terraces. At least two levels of terracing seem to be indicated on the slopes of the valley. Both represent levels of relatively slow accumulation of alluvial fans, which have been followed by periods of cutting in which the ends of the older fans have been sharply truncated. The levels of these terraces are about twenty feet and forty feet above the present floor of the valley. In the course of excavation of the valley, numerous landslides have evidently been an important feature in the move- ment of material from the walls of the bordering table-lands. On both sides of Virgin Creek numerous large blocks of the mesa with the basalt capping almost intact are seen in various 40 University of California Publications. [| GEOLOGY positions on the slope below the lava cap (pl. 11, fig. 1). On the edge of the mesa, blocks half a mile or more in extent may be seen in the first stages of movement. In the lower part of the valley near the union of Virgin Creek and Beet Creek a long series of lava-capped hills reaches for a distance of at least two miles from the mesa down to the present stream-bed (see pl. 5). The strata in these hills are frequently sharply inclined, usually with the dip toward the mesa (pl. 11, fig. 2). The lava capping consists of material identical with that in the basalt cap of the mesa. The separation of large blocks from the valley wall is evidently due in a considerable measure simply to the cutting of small streams, the basalt cap having protected the underlying mass until the wall was cut down to a very steep slope. The breaking away of blocks of large size is evidently assisted greatly by seepage developed through breaks in the lava cap. The presence of such channels of seepage on the mesas both north and south of Virgin Valley is evidently indicated by a series of peculiar lakes scattered over the table-lands. The lake basins, in some cases at least a mile in diameter, are situated on the level lava tables (fig. 4). They are usually approximately circular, with steep marginal walls formed by the basalt. Though the lava cap has disappeared over the area of the lake basins, there is no lateral outlet for wash. The only supposition on which we can account for the presence of these depressions seems to be that they have been formed by the sinking of the lake floor. This would most probably be caused by lines of seepage causing readjustment of the ash strata below, partly through the condensing effect of water on the beds of loose ash. Seepage of this character would also tend to separate large blocks from the main valley wall. Depressed areas, developed some distance away from the margin of the mesa, when reached by recession of the valley wall would presumably tend to move as large slides. In the movement of the numerous blocks which have been detached as slides from the mesa walls it is not improbable that earthquake shocks have played a part of some importance. In the fault movement which caused the four hundred foot displace- BULL. DEPT, GEOL. UNIV. CAL VOEMG PEN Ii! Fig. 1.—East end of mesa between valleys of Virgin Creek and Beet Creek, showing large blocks recently moved down from top of mesa. Fig. 2—Muceh disturbed masses of Virgin Valley Beds with lava eap- ping. Presumably representing old slides. Northwest side of valley of Virgin Creek. Vou. 6] = Merriam: Virgin Valley and Thousand Creek. 41 ment along the east side of Thousand Creek Ridge in post-Mesa Basalt time, earthquakes of considerable violence probably occurred. Suggestions of a stage during which considerable volumes of sediment may have accumulated in the valley before it had s -- Satace a a Sere Y oS ee TG sea — ove ti Fig. 4.—A portion of the mesa south of Virgin Valley. Antelope Butte, a prominent dome of rhyolite in the background, rises above the level floor of basalt. The circular lake in the foreground is surrounded by steep walls of basalt. attained as much as one-half. of its present depth are offered by a bed of gravel and boulders which covers the top of a prominent ridge in the angle between the drainage of Virgin Creek and Beet Creek (pl. 8). At this point the top of the spur running out from the sharp eastern point of the mesa is covered with at least fifty feet of coarse gravel and boulders. Farther east Mr. Heindl measured a section of this gravel one hundred and twenty feet thick. At some points near the east end of the ridge these gravels are interbedded with strata which appear like a part of the Virgin Valley Formation. Along a large portion of the north side of this ridge the contact between the gravel and the underlying Virgin Valley Beds is 42 University of California Publications. | GEOLOGY very clearly exposed, and a strongly marked angular uncon- formity of at least ten degrees variation in dip is shown. At some points the underlying strata are considerably contorted. The sharp minor folds might possibly be due to local slipping of soft strata below a contact with the gravels. The angular unconformity shown in a long exposure of the cliff can be interpreted only as the result of erosion preceding the deposition of the gravels. The gravel deposits resting upon the eroded Virgin Valley Beds consist almost entirely of large, well-rounded rhyolite fragments ranging up to more than two feet in diameter. The rhyolite closely resembles some of the flows in the formation forming the rim of Virgin Valley. A very few well-rounded pebbles of basaltic lava were obtained. Mr. Heindl, who has examined this basalt, finds it very different from the Mesa Basalt. While basaltic pebbles are rare in the mass of these gravels, large blocks from the basalt capping of the mesa near by are found resting on the top of the gravel beds. The unconformity of the rhyolitic gravels on the Virgin Valley Beds might be interpreted as meaning that it represents a stage of accumulation in a valley cut after the period of the Mesa Basalt flow. On the other hand it is noted that basaltic pebbles are quite rare in the rhyolitie gravels, while large masses of basalt from the edge of the mesa are found resting upon the top of these gravels. The edge of the basalt covering the mesa is near at hand, while the flows from which the rhyolite pebbles have been largely derived are much farther removed. It is moreover not probable that the few basaltic pebbles in the gravel are derived from the Mesa Basalt, and basaltic flows are presumably associated with the rhyolites below the Virgin Valley Beds. This evidence seems to show that the accumulation of the gravels occurred before the Mesa Basalt flow, otherwise there should be at least as large a percentage of fragments derived from the mesa cap as we find in other deposits known to have formed during the cutting of the present canon. The suggestion that the rhyolitic gravels accumulated at an early resting stage in the cutting of the present valley is probably further negatived by the presence of numerous large Vou.6] = Merriam: Virgin Valley and Thousand Creek. 43 land-slides between these gravel beds and the present bed of Virgin Creek. If at an early stage in its history, the main stream had occupied the position in which the gravels are now situated, it must since then have cut to the south and east across the present valley. If this had occurred, the numerous remnants of slides from the mesa wall, which he between the rhyolitic gravels and the present stream would necessarily have been removed. As a possible alternative the slides might be supposed to have travelled across the rhyolitic gravels and down into their present positions. This is certainly a violent assumption, as the slides are now separated from the mesa by one or two miles of relatively flat territory. The weight of evidence seems to indicate that the rhyolitic gravels were deposited after a short stage of erosion which occurred during the general period of sedimentation charac- terized as the Virgin Valley epoch. This theory receives support from an observation by Mr. Furlong, who has noted the oceur- rence of beds of gravel and boulders in the face of some of the exposures of the Virgin Valley Beds one or two miles north of the main occurrence of the gravels. The exposures observed by Furlong were at about the same general level below the mesa as the main outcrop of the rhyoltie gravels. The gravel and boulders were interbedded with the ash strata, and as nearly as the writer can judge from Furlong’s description they were of much the same nature as the main rhyolitic gravel outcrops. THOUSAND CREEK BEDS. In the region immediately to the east of Thousand Creek Ridge there are extensive exposures of mammal-bearing beds bordering the basin known as Thousand Creek Flats. Large outcrops of these beds are present along the eastern base of Thousand Creek Ridge, and similar beds reach for many miles north from Thousand Creek. A long, narrow, lava-capped mesa known as Railroad Ridge extending nearly north and south for six or seven miles into the Thousand Creek basin is composed of similar beds (pl. 2 and text fig. 5). To the north of the Thousand Creek basin, near a prominent point known as Oregon End, the sedimentary series of Thousand Creek Flats apparently 44 University of California Publications. | GEOLCGY extends under a mesa which corresponds in general to the table-lands in the Virgin Valley region. The capping of this mesa is similar to the Mesa Basalt in Virgin Valley. On the northwestern border of the basin large outerops of ashy beds, apparently representing the later Virgin Valley Beds, are visible beneath the basalt cap. To the east of Thousand Creek Flats the mammal beds come in contact with the upper portion of the Pueblo Range Series. The mammal beds here seem to extend ‘aga irasgi5Ne) CANON IOC E RALOLITE: THOUSAND CREEH BEOS BASALT. SECTIONC-D Fig. 5.—Seetion along the C-D line on plate 2, showing section from Thousand Creek Ridge to Railroad Ridge. in nearly horizontal position over to the contact with the rather steeply inchned upper beds of the Pueblo Range Series, so that the relation of the two groups of beds is apparently one of uncontormity. The principal exposures near Thousand Creek consist of tufaceous beds, ashes, and sands, ranging from white to red and dark brown. Many of the strata presumably represent ancient soil accumulations much like that covering the floor of the valley at the present time. Distinetly sandy layers appear a short distance below the top of the section at the northern end of the basin, and also in the beds at the southern extremity near Thousand Creek Ridge. A layer of white to gray ash, one to two feet thick, is exposed low in the section near Thousand Creek Ridge, and one is also seen in the beds at the northern end of the basin. The two may represent the same horizon, but they have not been traced through the series of exposures. Beds of gravel of considerable extent are also present. In some instances the eravels may represent terrace deposits of more recent age than the principal exposures of mammal beds in the basin. Both the southern and northern exposures in Thousand Creek basin are truncated by a terrace or mesa having approximately the same level as the top of Railroad Ridge. An exception to this is seen in a prominent hill which rises above this table and above Railroad Ridge in the northern exposures. BULL. DEPT. GEOL, UNIV, Exposure of Thousand Creek Beds. Northern portion of Thousand Creek basin. Vou.6] = Merriam: Virgin Valley and Thousand Creck. 45 Around the borders of Thousand Creek Flats there are several distinct terraces which are much below the level of the Railroad Ridge mesa, and are evidently of late Pleistocene age. They are shown in the broad flats situated just south of Railroad Ridge. This bench is about sixty feet above the present level of the stream bed and is apparently underlaid in a large part by undisturbed mammal beds. The Thousand Creek Beds are in general approximately horizontal, or dip shghtly toward the southwest; that is, toward Thousand Creek Ridge. In the exposures at the northern end of the section the strata are noticeably tilted, and the dip does not appear to be conformable with the plane of the terrace or mesa above. The nature of the beds exposed in Thousand Creek basin is In a general way similar to that of the sedimentary formation in Virgin Valley, though it does not repeat the characters of any particular portion of the Virgin Valley section. Possibly more sandy strata have been seen in the Thousand Creek section than were actually noted in the beds in Virgin Valley. If the Thousand Creek exposures represent the same epoch of deposition as those of Virgin Valley, it is evident from the contained fauna that they must correspond to the upper portion of the Virgin Valley Beds rather than to the lower portion of that section. So far as known, the mammal collections from the beds around Thousand Creek Flats all seem to represent one fauna, with the possible exception of a few remains obtained from deposits which occur on some of the lower terrace levels in the valley. The few specimens obtained from the terraces seem to represent a member of the horse group very near in its characters to the Quaternary genus Equus, whereas the other horse remains from the Thousand Creek exposures certainly represent an older group. As the remains from the terraces are fragmentary, it is possible that they do not actually represent forms very different from the other specimens, which are better preserved. It is also not at all certain that the deposits below the apparent terrace levels are distinct from the other Thousand Creek exposures. With the exception of the possible Quaternary remains from 46 University of Califorma Publications. | GEOLOGY Thousand Creek, the mammalian fauna which is found widely spread in the exposures of this region represents a stage of the late Tertiary, but apparently not the very latest portion of the Tertiary. In comparing the fauna of Thousand Creek with that of the Virgin Valley Beds, there are found to be a few species common to the two; but by far the greater number of the species, and even of the genera, are different. In most respects in which it is possible to make a comparison, the Thousand Creek forms are more advanced or more specialized than those of Virgin Valley. Judging by the fact that a few species are common to the two faunas, there is reason for considering them as not widely separated in time. On the other hand, it is difficult to place them in the same epoch, and it is evident that the Thousand Creek fauna is the later one. A summing up of the evidence presented by the Thousand Creek fauna with reference to the age in relation to that of the other formations of this region shows the following points: (1) The Thousand Creek fauna is of late Tertiary age; (2) It is later than the fauna obtained from the lower and middle Virgin Valley Beds; (3) It was not widely separated in time from the known Virgin Valley fauna, as there are a few mammalhan species common to the two. Although resembling the Virgin Valley Beds in a general way, it is evident from their contained fauna that the wide extent of exposures in which collections of fossil mammals have been made in the Thousand Creek region cannot represent the lower or middle portion of the section in Virgin Valley, in which the typical Virgin Valley fauna has been found. Unfortunately almost nothing is known of the fauna from the uppermost por- tion of the Virgin Valley section, possibly because the steep exposures immediately below the basaltic capping present a col- lecting area relatively much smaller than that representing the lower horizons. It is therefore necessary to reckon with the possibilty that the exposures at Thousand Creek represent the upper portion of the Virgin Valley section. If the Thousand Creek exposures be held to represent the uppermost portion of the Virgin Valley section, the present Vou.6] = Merriam: Virgin Valley and Thousand Creek. 47 position of the beds in the western part of the Thousand Creek region could be accounted for only on the assumption of very extensive faulting along Thousand Creek Ridge. The fossil- iferous beds immediately east of this ridge are now at least a thousand feet lower than the uppermost beds in Virgin Valley, while the drop of the mesa cap east of the fault-lne along Thousand Creek Ridge to the north amounts only to a little more than four hundred feet, which is not sufficient to account for more than half of the difference in position, even when original slope of the land and possible recent tilting of the whole region to the east are considered. The Railroad Ridge mesa, which contains some of the im- portant deposits of the Thousand Creek region, is capped with a basaltic lava which is considered by Professor G. D. Louderback and Mr. KE. L. Ickes, who have examined it, as representing the same type of rock as that in the Mesa Basalt. The capping of Railroad Ridge is about four hundred feet lower than that portion of the main mesa to the north, which has been faulted down to the east of the Thousand Creek Ridge fault. There is therefore some reason for considering that Railroad Ridge, and presumably the mammal beds exposed near it, belong to a block which has dropped very far below its original level. Mr. Heindl, who has examined the section of Railroad Ridge (see fig. 5, p. 44), finds the uppermost beds composed of very coarse gravels consisting of pebbles of rhyolite, basalt and obsidian, and has suggested that this ridge represents an ancient lava-filled river bed. The course of the ridge runs out from the vicinity of the existing canon of Thousand Creek, and would suggest a drainage passing near the line of the existing canon (see pl. 2). If the river bed was present immediately before the outpouring of the Mesa Basalt and before the later movements along the Thousand Creek fault, this portion of the lava flow might be presumed to have resisted erosion longer than the adjoining portions owing to the original greater thickness of the lava over the channel of the old stream. The idea that the Railroad Ridge lava represents the basalt filling of an old river bed also suggests that the Thousand Creek Beds might have accumulated in part from erosion of the western 48 University of California Publications. | GEOLOGY fault block previous to the outpouring of the Mesa Basalt. If extensive movement occurred along the Thousand Creek fault line before the outflow of the Mesa Basalt, accumulation may have taken place to the east of this line. During the time of such accumulation probably no deposits would be formed over the Virgin Valley region. Unless the whole region were reduced to the same level following such differential movement, one would expect to find the Mesa Basalt accumulating to much greater thickness east of the fault line, which is not clearly shown. A movement in pre-Mesa Basalt time, such as is suggested here, would presumably not result in more than a relative thickening of the beds to the east of the fault line, and possibly in a tem- porary interruption of sedimentation over the block west of the fault lne. Another possible explanation of the Railroad Ridge gravels, and of the Thousand Creek Beds in part or as a whole, is that they have been derived from the wash of Thousand Creek or other similar streams during the cutting of Virgin Valley. As a rough estimate, we may consider that at least ten cubic miles of rock have been carried out of Virgin Valley since the initia- tion of the cutting of the present valley. As nearly as one may judge, the distance to which this material could have been carried was short, and it could have been deposited over only a small area. It is therefore not improbable that some part of this material may have been deposited on the east side of Thousand Creek Ridge, particularly after the faulting move- ments occurred along the line of this ridge. According to the hypothesis just suggested, it would be neces- sary to consider either that the Thousand Creek Beds have been lowered by faulting since their deposition, or that they were accumulated very late in the history of the cutting of Virgin Valley. The beds forming Railroad Ridge are now far below the top of the mesa in Virgin Valley, and we can hardly imagine them as derived from the first sediment washed out in the cutting of the uppermost strata of the Virgin Valley Beds a few miles away and deposited in their present position. Without con- sidering that differential movement has changed the position of these beds in relation to the Virgin Valley Beds since their Vou.6] = Merriam: Virgin Valley and Thousand Crech. 49 deposition, it would be necessary to suppose the Thousand Creek Beds formed from sediment obtained during the cutting of the lower or later portion of Virgin Valley. The possibilities as to age of the Thousand Creek Beds with relation to the Virgin Valley Beds appear to be as follows: (1) They represent a portion of the Virgin Valley Beds faulted down into their present position. (2) They are younger than the Virgin Valley Beds, but older than the Mesa Basalt, and have been moved down by faulting. (3) They represent an aceumu- lation formed of the older wash derived from the post-Mesa Basalt erosion of the existing valleys of Virgin Creek and Beet Creek, or other similar drainage, and have since their aceumu- lation been dropped by faulting. (4) They represent an accumu- lation of sediment laid down during the period of erosion of the lower or younger portions of these valleys. (5) They are not a stratigraphic unit, and may be partly of the age of the Virgin Valley Beds and partly later. Without more detailed geologic information than it has been possible to obtain, it is not entirely clear as to which of these possibilities corresponds to the actual history. The first possibility has much in its favor, viz., that the Thousand Creek Beds represent a series of deposits which are comparable to the late Virgin Valley Beds and have been faulted down to their present position. The second case suggests a situation which is a possibility, though the evidence does not seem to indicate definitely that this has been the mode of accumulation of these beds. According to the third and fourth possibilities, v7z., that the Thousand Creek Beds represent an accumulation of wash carried out in the excavation of Virgin Valley and other valleys of approximately the same age, it must be presumed that the beginning excavation of Virgin Valley occurred a considerable time before the close of the Tertiary, as the Thousand Creek fauna antedates the end of the Tertiary. It would then be neces- sary to consider that the comparatively thin sheet of Mesa Basalt has been able to protect the Virgin Valley Beds beneath it from erosion through the whole of the Pleistocene and a part of Pliocene time, unless some later formation has in turn pro- 50 University of California Publications. [ GEOLOGY tected the Mesa Basalt. It seems improbable that the Mesa Basalt has been covered by considerable deposits of any kind, as the large level stretches now exposed appear to be entirely bare. There is strong evidence against the suggestion that the Thousand Creek Beds represent an accumulation of the latest wash from Thousand Creek and other similar drainage, as this would increase the length of the period back to the initiation of the first cutting through the Mesa Basalt. The strongest argu- ment in favor of relatively late age of the Thousand Creek Beds is obtained by Heindl’s study of the Railroad Ridge lava, and by his discovery of a basalt pebble in the gravel -immediately under the lava. The basalt pebble from the gravels below the lava is considerably decomposed, but seems to be rather nearer the type of the Mesa Basalt than it is to that of the older Pueblo Range lavas. Heindl has also called attention to the fact’ that the Railroad Ridge lava is not broken up as it might be if it were a block which had been dropped a considerable distance. In the absence of well preserved material, the basalt pebble from below the lava is hardly sufficient evidence to prove that the Railroad Ridge lava is a flow of later age than the Mesa Basalt. The lack of disturbance of the Railroad Ridge lava does not necessarily indicate that this block has not been moved, though minor disturbance might naturally be expected. Judging from the evidence of the fauna, it seems probable that the Thousand Creek exposures represent in the main a single period of deposition. Upon the lower terraces border- ing the valley there may be Pleistocene deposits with a fauna containing Hquus. Such deposits, if they occur, are apparently not thick, and their presence would hardly confuse the problem as to the age of the great extent of exposures with a late Tertiary fauna. It is very desirable that more evidence be obtained relative to the purely geologic history of the beds at Thousand Creek. A determination of the exact geologic position of these beds may depend finally upon a study of the fauna, but from the standpoint of the palaeontologist it is most desirable to have the evidence of sequence of faunas based upon stratigraphic succession. Vou.6] Merriam: Virgin Valley and Thousand Creek. 51 HIGH ROCK CANON EXPOSURES. About thirty miles southwest of Virgin Valley a number of exposures were found to contain a fauna similar to that of the Virgin Valley Beds. The localities at which collections were made are near High Rock Canon and Little High Rock Canon (see pl. 1). The beds in which the mammalian remains were obtained con- sist of ashy or tufaceous materials resembling some of the ex- posures in Virgin Valley. The region bordering the valley in which the mammal beds appear is largely lava-covered, and according to Heindl and Furlong the fossil beds appear to dip under the lavas at some localities. Whether the apparent posi- tion of the lava over the mammal beds is an original strati- etaphie relation is uncertain, as there is considerable faulting ‘in this region. The nature of the lavas here is not certainly known, but a rhyolite seems to form the greater part of the out- “crops. SS aire UWS ee as ON I eee 7 0 SO! 60: «C= Oe wR o> oO: Om) 0 0 °\O © oS 0 SLO 0 oo f ALLUVIU tS Some me =) eae be LZ \E\ COs es \ I: \ LY RYN | SS NUK NN SS SS ¥ < } es \} — tes Ve We {\ . iN ISS MY) ) Ve : We ( | le = ay Yf, ©) Stupstowe | : | A OF THE ———— | SARGENT | = — ) OFELD == | FIELU i= CALIFORNIA poco: ) otas ee ieee = Ey Spee’ 1% Y OF CALIFORNIA PUBLICATIONS - BULLETIN OF THE DEPARTMENT OF > Re GEOLOGY .6 No. 4, pp. 79-87 Issued February 4, 1911 ae ADDITIONS TO THE AVIFAUNA _ PLEISTOCENE DEPOSITS AT FOSSIL LAKE, OREGON ee BY _*- LOYE HOLMES MILLER . BERKELEY THE UNIVERSITY PRESS By. ae Ming hd ic x gy aaa Cate Pees tt Bah 0 lr" nif cations of learned societies and institutions, universities and ! all the publications of the University will be sent upon request. For sample ¢ publications and other information, address the Manager of the University fe California, U. S. A. All matter sent in exchange should be addressed to Department, University Library, Berkeley, California, U.S. A. ° Geology.—AnprEw C. LAwson and Jon C. Murriam, Editors. Price per volume, $3. 13. 14, iw) . The Geology of Carmelo Bay, by Andrew C. Lawson, with chemical analyses aa ; ‘ pee) . The Soda-Rhyolite North of Berkeley, by Charles Palache - The Hruptive Rocks of Point Bonita, by F. Leslie Ransome . The Post-Pliocene Diastrophism of the Coast of Southern California, by Andrew GO. . The Lherzolite-Serpentine and Associated Rocks of the Potrero, San Francisco, ne . On a Rock, from the Vicinity of Berkeley, containing a New Soda Amphibole, by ; . The Geology of Angel Island, by F. Leslie Ransome, with a Note on the Radiolarian . The Geomorphogeny of the Coast of Northern California, by Andrew C, Lawson. . On Analcite Diabase from San Louis Obispo County, California, by EE Ww. . On Lawsonite, a New Rock-forming Mineral from the Tiburon Penigeaie, Marin . Critical Periods in the History of the Earth, by Joseph Ledente: Tilasonohues ee . On Milignite, a Family of Basic, Plutonic, Orthoclase Rocks, Rich in Alkalies and . Phe Geology of Point Sal, by: Harold W. Pairbanks.-.2) 22). ee eee . On Some Pliocene Ostracoda from near Berkeley, by Frederick Chapman.................. . Note on Two Tertiary Faunas from the Rocks of the Southern Coast of Vancouver . The Distribution of the Neocene Sea-urchins of Middle California, and Its Bearing . The Geology of Point Reyes Peninsula, by F. M. Anderson.........::-:e-sseceseseceseeceneereeees . Some Aspects of Erosion in Relation to the Theory of the Peneplain, by W. S.. . A Topographie Study of the Islands of Southern California, by W. S. Tangier Smith . The Geology of the Central. Portion of the Isthmus of Panama, by Oscar H. Hershey . A Contribution to the Geology of the John Day Basin, by John C. Merriam.......... _ Mineralogical Notes, by Arthur S. Waikele 2202) oe ceo caeteee epee ee ea . Contributions to the Mineralogy of California, by Walter C. Blasdale . The Berkeley Hills. A Detail of Coast Range Geology, by Andrew C. Law and * Nors.—The University of California Publicati Orro HARRASSOWITZ R. FRIEDLAENDER & Soun C LEIPZI¢ BERLIN Agent for the series in American Arch- Agent for the series in Americ aeology and Ethnology, Classical Philology, aeology and Hthnology, Botany, — Education, Modern Philology, mage oe Mathematics, Pathology, Physic Psychology. Zoology, and Memoirs. ee a Volumes I (pp. 428), II (EP. 450), III (pp. 475), IV (pp. 462), V (pp. 448), = completed. Volume VI (in progress). _ 4a Cited as Univ. Calif. Publ. Bull. Dept. Geol. ’ VOLUME 1. Oa wenn en ne nn nn nen nnn een ne nnenenes cooperation in the field, by Juan de la C. Posada Waiwsotn:?. 22. ots on he ee Ss a Cae ae Se Sa Aci alan ae Charles Palache. Charles Palache. : jee’ Nos. 5. and, 6 im OM€ COVE? -.2 2 cee fiscesencceccereccee mc ncencerecoereeecnenre ee Chert from Angel Island and from Buri-buri Ridge, San Mateo County, California, by George Jennings: Hinde <._... 0 .ege eee es ee 45 Fairbanks County, California, by» FE. Iueshe: Ransome. 323. 22 3 ee ee Lime, Intrusive in the Coutchiching Schists of Poohbah Lake, by Andrew —_ Cis Wanson: 2.....8 Bete SA ene ee 2 ee aur Sigmogomphius LeContei, a New Castoroid Rodent, from the Pliocene, near : Berkeley, by John C. "Merriam... $0. ug ee The Great Valley of California, a Criticism of the Theory of Isostasy, by F POTseglie RANSOME -.nctcs tess. 22csce-chendo- dade eSesacste en teacie not epe a: ep nate at ee VOLUME 2. Istand;, by...J.,C: “Merriam 2:08. 0a Be ee Dee ee ee on the Classification of the Neocene Formations, by John C. Merriam...........2.... Tampier: Smith cna cos se a Ee nS Charles’ Palache «.--..:1.-.--:-.. deeccseteceeecenecenaecnnanenneesnecennaeannasensneecaaneeseceneceonscenaseennsrensseeeecetonsee . UNIVERSITY OF CALIFORNIA PUBLICATIONS BULLETIN OF THE DEPARTMENT OF GEOLOGY Vol. 6, No. 4, pp. 79-87 Issued February 4, 1911 ADDITIONS TO THE AVIFAUNA OF THE PLEISTOCENE DEPOSITS AT FOSSIL LAKE, OREGON BY LOYE HOLMES MILLER. 7 ae CONTENTS. ae TULANE ECR Tae ca ey nr 5 Pee eg Rr ee See ee nee eee ee 79 Source and nature of the material —........2..202o 80 Previous knowledge of the fossil avifauna -~............... ee ON Ae Rae 81 List of species known from Fossil Lake .............-.-..-2--22.-----2eeeeeeeeeeeeeee 82 DES CHI TOMERO THES CCUCS: essence rs cccacs ato. 2 oS sen Sess acne 22 ass -seiacustgentas¢eisesefeses¢eesse-eebezesz 3 ZAK) at toa) 0) Oo EAWESY UICC AN 5) 0 epee aera ee eee ee 83 Hrismatura Jamaicensis (Gmelin) -...2.2.2...20c.eccccceeceenceseceeee cee cneeeeenee nee 86 Chinois Loyreoksyoyamtwisy (UD a uae NeyyS)) eee 86 INTRODUCTION. The horizon designated as the Equus Beds in the Fossil Lake? region of Oregon has been known to palaeontologists for many years, and the field has been extensively worked by Marsh, Cope, Condon, Sternberg and the University of California. The ma- terial representing the bird group has been so critically examined, by both Cope and Schuffeldt, that it would seem as though our knowledge of the Pleistocene avifauna of that region bore little chance of improvement. It is the object of the present paper to record certain additions to the known list of species that have recently come to hght. 1 Generally known in the literature as ‘‘Silver Lake’’. Fossil Lake is a small body of water about twenty miles north-east of Silver Lake. 80 University of California Publications. | GEOLOGY SOURCE AND NATURE OF THE MATERIAL. During the summer of 1901 an expedition organized and financed by Miss Annie M. Alexander visited the Fossil Lake region for the purpose of collecting vertebrate fossils from the Pleistocene beds. The collections resulting from this expedition were generously donated to the University of California and form part of its collections in vertebrate palaeontology. The material assembled consists largely of mammalian re- mains. There are, however some representatives of the fishes,” and a very interesting collection of bird material. The avian re- mains were first placed by Professor John C. Merriam in the hands of Mr. F. A. Lueas for determination and description. Unfortunately that able student of avian osteology was prevented by the pressure of other duties from giving the collection more than a cursory examination, and after retaining the material for some time he returned it to the University with a purely tentative identification of the various species represented. After the lapse of a number of years, the task is assumed by the present writer, who wishes to acknowledge his indebtedness to Mr. Lucas for the suggestions conveyed by the determinations made by him several years earlier. With the exception of several coracoids and two scapulae, all the determinable material consists of limb bones, with a surpris- ing paucity of the dense tarso-metatarsi. Various possible ex- planations for this scarcity of tarsi suggest themselves. The most plausible is here offered. On lakes or other large bodies of water the remains of aquatic birds tend to concentrate along the shore- lines. Owing to the buoyant effect of the air stratum retained within the feather coat, the body may float for a prolonged period or until cast upon shore by the prevailing wind. The naked shank is submerged during this time, as a rule, and is subject to more rapid maceration and to the attacks of water fleas or the aquatic larvae of insects. These influences tend to accelerate dis- articulation by loss of the binding ligaments. The metapodials would therefore be sown broadcast over a wide area; a result 2 See Jordan, David S., Fossil Fishes of California. Univ. Calif. Publ. Bull. Dept. Geol., 5, pp. 95-144. 1907. (ee) — VoL. 6] Miller: Avifauna of Fossil Lake. quite at variance with the concentration of other remains upon the lee shore. Instances in support of this view are abundant in the experiences of the author while collecting the skeletons of sea birds cast upon the beach. The ligaments of the foot and shank are among the first to loosen, making these the parts most frequently wanting in the beach specimens. It is otherwise dif- ficult to account for the preservation of such fragile bones as the pheumatie coracoid, while the dense, strong tarsus is so sparsely represented in the assembled material. The specimens composing the collection are in a beautiful state of preservation. Where not actually fractured, the form and markings are almost as perfect as though freshly macerated from the Recent specimen. This shows particularly well in such a specimen as the femur of a grebe, where the rugosities are normally so well defined. The cavities of the long bones and the spaces of the cancellated bone where broken are commonly filled with fine yellowish gray sand, which formed the matrix in which they were buried. PREVIOUS KNOWLEDGE OF THE FOSSIL AVIFAUNA. The fossil avifauna previously known from the Fossil Lake Beds has been discussed very thoroughly in an extensive memoir by Schuffeldt®? embodying the results of his examination of the private collections of Cope and Condon. These collections were more extensive than the one at present under discussion. As might be inferred, therefore, the number of species determinable in the California collection is less than that determined by Schuffeldt. There are represented, however, three forms not reported by Schuffeldt, one of which, a species of .Echmophorus, is new to science. The age of the Fossil Lake Beds was assumed by Schuffeldt to be Pliocene. This was the estimate made by Cope from a study of the mammalian fauna, which he correlated with the Subapennine of Europe. The more extended study of various western horizons made by other writers has unquestionably proven the Pleistocene age of these beds. 2 Sehuffeldt, R. W., Journ, Acad. Nat. Sci. Phil., no. 9, p. 889. 1892. 82 University of California Publications. [ GEOLOGY LIST OF SPECIES KNOWN FROM FOSSIL LAKE. Schuffeldt enumerates forty-nine species in his discussion of the avifauna as determinable from the two collections examined by him. A list of these species is as follows: SPECIES RECORDED BY SCHUFFELDT. Pygopodes LEchmophorus occidentalis (Linnaeus). Colymbus holboeli (Reinhardt). Colymbus auritus Linnaeus. Colymbus nigricollis californicus (Brehm). Podilymbus podiceps (Linnaeus). Longipennes Larus argentatus Pontoppidan. Larus robustus Schuffeldt. Larus californicus Lawrence. Larus oregonus Schuffeldt. Larus philadelphia Ord. Xema sabini (J. Sabine). Sterna elegans Gambell. Sterna forstert Nuttall. Hydrocheledon nigra surinamensis (Gmelin). Steganopodes Phalacrocorax macropus Cope. Pelecanus erythrorhynchos Gmelin. Anseres Lophodytes cuculatus (Linnaeus). Anas platyrhynchos (Linnaeus). Mareca americana (Gmelin). Nettion carolinense (Gmelin). Querquedula discors (Linnaeus). Querquedula cyanoptera (Vieillot). Spatula clypeata (Linnaeus). Dafila acuta (Linnaeus). Aix sponsa (Linnaeus). Marila valisneria (Wilson). Glangula islandica (Gmelin). Harelda hyemalis (Linnaeus). Anser condoni Schuffeldt. Anser albifrons gambelli Hartlaub. Branta hypsibatus Cope. Branta canadensis (Linnaeus). Branta propinqua Schuffeldt. Chen hyperboreus (Pallas). Olor paloregonus Cope. Odontoglossae Phoenicopterus copei Schuffeldt. Herodiones Ardea paloccidentalis Sehuffeldt. Palaudicolae Fullica americana Gmelin. Fullica minor Schuffeldt. Limicolae Lobipes lobatus (Linnaeus). Vou. 6] Miller: Avifauna of Fossil Lake. 83 Gallinae Tympanuchus palidicinctus (Ridgeway). Pediacetes phasianellus columbianus (Ord). Pedicecetes nanus Sehuffeldt. Palaeotetrix gilli Schuffeldt. Accipitres Aquila pliogryps Schuffeldt. Aquila sodalis Schuffeldt. Striges Bubo virginianus (Gmelin). Passeres Euphagus affinis Schuffeldt. Corvus annectens Sehuffeldt. ADDITIONAL SPECIES IN THE CALIFORNIA COLLECTIONS. Pygopodes Achmophorus lucasi, n. sp. Anseres Erismatura jamacensis (Gmelin). Accipitres Cireus hudsonius (Linnaeus). DESCRIPTION OF SPECIES. ZECHMOPHORUS LUCASI, n. sp. Type specimen! no. 12605, Univ. Calif. Col. Vert. Palae., and cotypes nos. 12603 and 12604. Femur larger than in 4. occidentalis and less curved in the anteroposterior plane. Tarsus stouter in the shaft, with nar- rower extremities, and with narrower intereotylar tuberosity. In examining a group of six grebe femora in the collection there readily appeared a division of the group into two series. One, embracing two specimens, corresponded in every particular with the existing species; the other, consisting of four speci- mens, showed constant characters which were distinctly different from the Recent form. The difference in size is evident upon examination of the table of measurements recorded below. The osteological characters are not at variance except as relates to the degree of curvature of the shaft. The character is not such a one as is readily measured but is easily evident on placing to- gether bones from the two species. The tarsus of the new form is represented by four specimens. One is perfect except for the loss of the middle trochlea; the others consist of two proximal and one distal fragment. The deviation from the existing species is here noticeable in the proximal end of the bone. The tarsus of 4G. lucasi is actually longer and the shaft stouter, but the head is quite ap- preciably narrower. This compression of the head region has the effect of reducing also, the width of the intercotylar tuberosity—a character at 41 take pleasure in naming this species in honor of Mr. F. A. Lucas, in whose hands this collection was originally placed for examination. CO 4 University of California Publications. | GEOLOGY once noticeable on comparing the tarsi from the anterior aspect. There is noticeable also an elevation of the inner border of the inner tibial facet to a degree exceeding that seen in the existing species. The anterior border of the shaft in 4. occidentalis is almost perfectly straight, whereas the same profile in 4. lucasi is decidedly convex. The coracoid assigned to this species is distinguishable from that of the existing form by its greater length and its very slender shaft. In total length along the inner border, the cotype exceeds the Recent species by three and seven-tenths (3.7) millimeters. The actual transverse diameter of the shaft is, however, three-tenths (0.3) millimeters less at its narrowest point. Figs. 1 and 2.—4#chmophorus lucasi. Femur, natural size. Fig. 1, posterior view; fig. 2, lateral view. Fig. 3—A#chmophorus lucasi. Tarsometatarsus, anterior view, natural size. The several differences between the extinct form and the liv- ing one seem to point toward the former as a bird of slightly larger body size, as indicated by the longer coracoid; but pos- sibly of weaker powers of flight, as is suggested by the slender- ness of that bone. The swimming powers may have been greater, since the posterior limb shows greater robustness of its proximal segment, the femur, and greater length of its distal segment, the tarsus. VoL. 6] Miller: Avifauna of Fossil Lake. 85 A table of comparative measurements of the two species is given below. The Pleistocene form of .6 in one’ covers: ales 5 ee 4 aie 2 7. The Geology of Angel Island, by F. Leslie Ransome, wail a Note c onl ‘he Radidlatian ; Chert from Angel Island and from Buri-buri Ridge, San Mateo Co. ty, Califeriia, ah se ‘ Phy George Jennimas Hinde 4s...) ee 5. iba: ee eae «5 aaa a me 8. The Geomorphogeny of the Coast of Northern California, by rons : OL Laxyson le, 3g Rees 9. On Analcite Diabase from San Louis Obispo County, Calitocnin bv Warold we ; ave eHainbaiikes eae tla we tS pe oe ee SI ee ee me! et ‘ 10. On Lawsonite, a New Rock-forming Mineral from the Tiburon P Bumets) hes hye Thar f ‘ oe as a County, California, by F. Leslie Ransome. .2 2 -2.-.-..2scccccieeee eee 4 Ria ote Sea : _ 11. Critical Periods in the History of the Earth, by Joseph LeConte... fet, : 12. On Malignite, a Family of Basic, Plutonic, Orthoclase Rocks, Rich \ Usside ‘enact ay: _ Lime, Intrusive in the Coutchiching Schists of Poolibag ee yy Andrey wm Cc. Lawson ‘ # KG 13. Sigmogomphius LeContei, a New Castorotd Rodent, from the Berkeley, by John C. ‘Merriam Bee te er een at ance ete oa 14. The Great Valley of California, a Criticism at the Theory of Tsostas Leslie SEE Fe A Rate AM Ne Mire A ne SM Pain Been SE VOLUME 2.° 1, The Geology of Point Sal, by Harold W. Fairbank ...8 ok 2. On Some Pliocene Ostracoda from near Berkeley, by Frederick Chapm: 8. Note on Two Tertiary Faunas from the Rocks of the Southern Coast of V an i j Msland,< by. JicCs, Merriam: 22 2 nose oh eis re eee ee ; 4, The Distribution of the Neocene Sea- urehins of Middle California, and Its on the Classification of the Neocene Formations, by John C. Merriar iP 2, 5. The Geology of Point Reyes Peninsula, by F. M. Anderson. ‘3 6. Some Aspects of Erosion in Relation to the Theory of ti . : AME aX a(S Det) 0a ab eRe ae RA eae See oe ube Se 7. A Topographic Study of the Islands of Southern Californ: % 8. The Geology of the Central Portion of the Tsthmus of Pana: ‘9. A Contribution to the Geology of the John coe ‘Bas in, b; 10. Mineralogical Notes, by Arthur S. Hakle... 11. Contributions to the Mineralogy of Califo 12. The Berkeley Hills. A Detail of Coast Re ---——s Chariles Palache UNIVERSITY OF CALIFORNIA PUBLICATIONS BULLETIN OF THE DEPARTMENT OF GEOLOGY Vol. 6, No. 5, pp. 89-161, pls. 19-28 Issued February 28, 1911 THE GEOMORPHOGENY OF THE SIERRA NEVADA NORTHEAST OF LAKE TAHOE. BY JOHN A. REID Epitor’s Note.—John A. Reid died on July 4, 1909. As a candidate for the degree of doctor of philosophy in the University of California he had chosen for his thesis the study of the structure of the Sierra Nevada northeast of Lake Tahoe, and at the time of his death left a manuscript setting forth the results of his investigations. The manuscript was nearly ‘ready for the printer, but some details were lacking; it was his evident intention to supplement it in some parts, rearrange it in others, and to make some illustrative sectional drawings. I had been in consultation with him during the progress of his work, and had once visited the field in his company and there discussed various points with him. After his death his widow sent the manuscript to me for revision, and it has been my sad pleasure to perform this service for my departed friend. When the geo- logical history of the Sierra Nevada is finally written, this paper of Reid’s will occupy the important place always given in science to the pioneer who breaks the way to new truth. I know of no paper in recent years dealing with mountain structure that shows so much ability and insight in the interpretation of complicated faulting and its expression in geomorphy as the one here presented.—A. C. L. 90 University of California Publications. [GEOLOGY CONTENTS. PAGE Introd ctions 25. s Ante eae ee ere 90 Petrography and Geological Relationships 2.20000... 92 The Bedrock Complex 92 Granodiorite Schists: one 94 hes Irnuptive Contact 22s. cases eee reeeerrere cee 95 Mhe Toot of the Batholith: 22222022 esss eer eee 97 MH SUperjacemt Serves s cece coco oe esses ee eee ee 97 Raver (Gra Vell S) vex cecssc20ccececbe-ceceseccunttieecenes osetia 97 Wolcamies: co.cc eee ee eee eee 99 O71 0), = a rp ree 100 PIG CHSCOMCs - sacsx-cecee eset egett ee sapaseads sheen avert eae 100 B06 (<3; ne eee a ees 100 BUS AG oe 2 aoe woes eatseeea sate ee eee ce ceenae raat nee seen ye Other: Rocks eis wes eee ee eee eee eee Relative Age of the Superjacent Series —......1..0..22..2.2csseseceeeeeeeeeeeeee Influence of Rocks upon the Geomorphy .............--..- tno JiOUMES? Sook. 2 soe Seo cess see es cate scans oo ecsec oc seeeeeweees eet eee SWiG aC Tit Ong sere case. cscs teteceevaneseeesees saee tence sec ees peeeeeess ee Topographic: Divisions) sess secceseee secves Sons ee ea rece eee sesso ae eee GeEOTMOM PD Ty. Perea esas ac coscbe ne bee Segee ccs ve cc Nome sez see sees uneeee2cusdeteedec esate ee Te he: Summit! Zone: 2.225. s.t nsec ee eee sees ee TT Whe Ho he Pilattea tes acc -cteenes a scbecsseaacs trate cs secs es eee eee eer Significance of Summits and Plateau ........20200.2..2.eseeeeeeeeee eee JTS Whe Malt, (ome. 25 os ioscan es eee ee Detailed Description of the Fault Zone .........2....2..2.22..22220222-0seeeeee The: Carson ATGa,, 2220.2 ree ee The -Brank town! -Ame@ay 2.2 coco iez acess cessc 2 secncnete seees seaetsaaeeseseee ee MheGenoa AN Ca, 22 2 css feces see ener ee Summatiom Of Wopo owe p ly. se cee ssece eer acer eee cree ees 135 TV... The. Valley Zone 22.2.2. ens ie te ee ee ee 136 Important Features of the Nevada Ranges ......-....2...2..2-.-2------2seeeeeee 139 Relative Ages of the Faults —.............2-.22:--::-200200-+ Structure and Genesis of Little Valley Summary of Sequence of Wauilts 222.2 o2o.cc2cccieccecceccceesncscceesereeeaeeees Other Important Structural Features Elsewhere ..............2...22..222.00-10--0-+- 159 Carson and Truckee Rivers ........ govecdegesesace3esesudetsienstese_csesediva.i2s..icieseeees 159 INTRODUCTION. There exist in that portion of the Sierra Nevada northeast of Lake Tahoe several very peculiar geomorphic features that call for explanation. Of these Little Valley, an elevated longitudinal valley within the range west of Washoe Lake, is at first glance Vou. 6] Reid: The Geomorphogeny of the Sierra Nevada. 91 the most important. Q a. a naif Volca: Bas Pitel | SWE LRAT re UNIVERSITY OF ‘CALIFORNIA PUBLICATIONS Svat yy A “BULLETIN OF THE DEPARTMENT OF GEOLOGY . 6, Nos. 6 and 7, pp. 163-169, pl. 29 Issued April 18, 1911 PLEISTOCENE OF RANCHO LA BREA BY JOHN C, MERRIAM FROM TERTIARY BEDS ON THE MOHAVE DESERT JOHN C. MERRIAM «i : APR 26}911 Ni; Z “diong| MuseO™ BERKELEY _ THE UNIVERSITY PRESS cations of learned societies and institutions, universities and libra all the publications of the University will be sent upon request. publications and other information, address the Manager of the Universit California, U. S. A. All matter sent in exchange should be ane to Note.—The Tnteseetee of California Publications are 0 ed in Department, University Library, Berkeley, California, U. S. A “a Orro HARRASSOWITZ R. iit ae & si a LEIPZIG — BERLIN ~ Agent for the series in American Arch- Agent for the series in Ame Geology.—ANnpDrew C. Lawson and JoHN C. Merriam, Editors, Price per volam 13. 14, wo . The Geology of Carmelo Bay, by Andrew C. Lawson, with chemical analyses 2 . The Soda-Rhyolite North of Berkeley, by Charles Palache..........-. Paes . The Eruptive Rocks of Point Bonita, by F. Leslie Ransome.........--20..-.20.- . The Post-Pliocene Diastrophism of the Coast of Southern California, by Andrew . The Lherzolite-Serpentine and Associated Rocks of the Potrero, San Francisco, by . On a Rock, from the Vicinity of Berkeley, containing a New Soda Amphibole, by 3 Charles Palache. ¢ Noss ov and. 67 in’ one" cover..-252 <5 eee Ee bach asgt hvac hi, Ue eae . The Geology of Angel Island, by F. Leslie Ransome, with a Note on the Radiolarian - . The Geomorphogeny of the Coast of Northern California, by Andrew C. Lawson... . On Analcite Diabase from San Louis Obispo County, Calories by Harold W. — . Critical Periods in thé History of the Harth, by Joseph LeConte......... taser tS . The Distribution of the Neocene Sea-urchins of Middle California, and Its Bearing . The Geology of Point Reyes Peninsula, by F. M. Anderson . The Berkeley Hills. A Detail of Coast Range Geology, by Andrew C. Lawson aeology and Ethnology, Classical Philology, aeology and Ethnology, Botan Education, Modern Philology, Philosophy, Mathematics, Pathology, Psychology. Zoology, and Memoirs. Volumes I (pp. 428), II (pp. 450), III (pp. 475), IV (pp. 462), V (pP- 448; completed. Volume VI (in progress). Cited as Univ. Calif. Publ. Bull. Dept. Geol. VOLUME 1. * - » cooperation in the field by Juan de la C.. Posada’ 1...-22..2020ee ieee Bawsons: 22.320) Pie on ee A a ee er Charles Palache. Chert from Angel Island and from Buri-buri Ridge, San Mateo County, California, | by George: Jennings: Hinde y...-.5. cc ear ae een Mairban kes... 22252 os eee Fes ease a a ce Si ee ee ax, On Lawsonite, a New Rock-forming Mineral from the Tiburon Peninsula, Marin County, California, by F. Leslie Ransome. On Malignite, a Family of Basic, Plutonie, Orthoclase Rocks, Rich in Alkalies and Lime, Intrusive in the Coutchiching Schists of Poohbah Lake, by Andrew C. Lawson nace aR ERS, SN Sipe NE Te Ie Sigmogomphius LeContei, a New Castoroid Rodent, . Berkeley, by John C. Merriam--\......2.-.-------------c0se--= The Great Valley of California, a Criticism of the Thee: of Toone by FE. Theslie: Ramsome © .22.212.-..-2.ci- race ---nae-neoner cent ee cenen -Oce cee eden cae ted etna on en ese e geo menses n= se VOLUME 2. The Geology of Point Sal, by Harold W. Fairbanks......-...-.--2--2--- On Some Pliocene Ostracoda from near Berkeley, by Frederick Chapman Be oe. Note on Two Tertiary Faunas from the Rocks of the Southern Coast of Vancouver Island, by J. C. Mervin... cn cscccccscccccecccecececeneececcen este sec ecteeeecnneeneneme ene eesceenansaneeneneae on the Classification of the Neocene Formations, by John C. Merriam Some Aspects of Erosion in Relation to the Theory of the Peneplain, by Ww.” 8 ia Tangier Smith on... cee eee ees teceeceececeee ce ecet cone eeeeceterecen een encesee ceenenccoac sar caanenatasseonnsae ie A Topographic Study of the Islands of Southern California, by W. S. Tangier Smi th 64 The Geology of the Central Portion of the Isthmus of Panama, by Oscar H. Hershey 3 A Contribution to the Geology of the John Day Eau, by John C. Merriam......... ee Mineralogical Notes, by Arthur'S. Hakle 2 Contributions to the Mineralogy of California, by Walter C. Blasdale Gharles: Palache .6..%. 3 Se ere ee eee UNIVERSITY OF CALIFORNIA PUBLICATIONS BULLETIN OF THE DEPARTMENT OF GEOLOGY Vol. 6, No. 6, pp. 163-166 Issued April 18, 1911 NOTE ON A GIGANTIC BEAR FROM THE PLEISTOCENE OF RANCHO LA BREA BY JOHN C. MERRIAM. With the exception of a single tooth obtained by the writer during his first examination of the Los Angeles asphalt beds in 1906, no remains representing the bear family are known to have been obtained from Raneho La Brea until very recently. Issued June 28, 1911 BY f ROY E. DICKERSON \ ‘ p. ‘ “ ra : Xs 7 ce : - F; ot ee : : Ets insti, : BERKELEY yl O isd THE UNIVERSITY PRESS Nae eee oa /0 (Os Aon me ; nal Museo rt \ Note.—The University of California Publications are offered in cations of learned societies and institutions, universities and libra: all the publications of the University will be sent upon request. For samy publications and other information, address the Manager of the University California, U. S. A. Ali matter sent in exchange should be addressed to Department, University Library, Berkeley, California, U. S. A. — i \ OTTo HarRassowiTz R. FRIEDLAENDER & § LEIPZIG - BERLIN Agent for the series in American Arch- Agent for the series in An aeology and Ethnology, Classical Philology, aeology and Ethnology, Bota Edueation, Modern Philology, Philosophy, Mathematics, Pathology, — Psychology. Zoology, and Memoirs, 3 . Geology.—ANnprrew C. Lawson and Joun OC. Merriam, Hditors. Price per vol Volumes I (pp. 428), II (pp. 450), TIT (pp. 475), IV (pp. 462), V (pp. completed. Volume VI (in progress). : Cited as Univ. Calif. Publ. Bull. Dept. Geol. VOLUME 1. . : 1. The Geology of Carmelo Bay, by Andrew C. Lawson, with chemical analyses cooperation in the field by Juan de la C. Posada 2. The Soda-Rhyolite North of Berkeley, by Charles Palache 3. The Kruptive Rocks of Point Bonita, by F. Leslie Ransome................ = : 4. The Post-Pliocene Diastrophism of the Coast of Southern California, by Andrew Aa SOM. Fie oe Se Nels SRN oe, | Guat ae Oe tie e 3 Le fe: 5. The Lherzolite-Serpentine and Associated Rocks of the Potrero, San Francisco, Charles Palache. ; E 6. On a Rock, from the Vicinity of Berkeley, containing a New Soda Ammnhibo Charles Palache. Nos. 5 and, 6h2n,o0ne- cover:.2250. oe a ie 7. The Geology of Angel Island, by F. Leslie Ransome, with a Note on the Radio Chert from Angel Island and from Buri-buri Ridge, San Mateo County, Californ by:George: Jennitigs Hinde :..2v.. io see ee ee 8. The Geomorphogeny of the Coast of Northern California, by Andrew C. Lawson 9. On Analcite Diabase from San Louis Obispo County, California, by Harold Mairbanikes | yes SP Ne ee Ne a, og Sa eae a Tai 10. On Lawsonite, a New Rock-forming Mineral from the Tiburon Peninsula, County, California, by F. Leslie Ransome...........-- oe a oe ee 1]. Critical Periods in the History of the Earth, by Joseph LeConte..... 12, On Malignite, a Family of Basic, Plutonic, Orthoclase Rocks, Rich in Alkal Lime, Intrusive in the Coutchiching Schists of Poohbah Lake, by Andre Cy): LoawSom® 234025 ee CS - De 13. Sigmogomphius LeContei, a New Castoroid Rodent, from the Pliocene, Berkeley, Joy. Jol C22 Merrie mi cect cee ae ae arene ee Sem SS 14. The Great Valley of California, a Criticism of the Theory of Isostasy, by eslie “Ransome «cites. 25... kA ee see oe a VOLUME 2. 1. The Geology of Point Sal, by Harold W. Fairbanks... 0.2 ee On Some Pliocene Ostracoda from near Berkeley, by Frederick Chapman... 3. Note on Two Tertiary Faunas from the Rocks of the Southern Coast of Vancouve Tisland,. “by. sJe s@} Merial ame oe ae esc eee epeccn ass eS eee 4, The Distribution of the Neocene Sea-urchins of Middle California, and Its Bearing on the Classification of the Neocene Formations, by John C. Merriam. a 5. The Geology of Point Reyes Peninsula, by F. M. Anderson.................... 6. Some Aspects of Erosion in Relation to the Theory of the Peneplain, by W. Mamorver: (Sri soc phe ee ee ei A Topographic Study of the Islands of Southern California, by W. S. Tangier The Geology of the Central Portion of the Isthmus of Panama, by Osear H. Hers. 9. A Contribution to the Geology of the John Day Basin, by Jehn C. Merriam. 10. Mineralogical Notes,-by Arthur S. Hakle 2.2.2 ) eee 11. Contributions to the Mineralogy of California, by Walter C. Blasdale.. 12. The Berkeley Hills. A Detail of Coast Range Geology, by Andrew C. L ws Charless Patleic a es soos oe a ee oe iS UNIVERSITY OF CALIFORNIA PUBLICATIONS BULLETIN OF THE DEPARTMENT OF GEOLOGY Vol. 6, No. 8, pp. 171-177 Issued June 28, 1911 THE STRATIGRAPHIC AND FAUNAL RELA- TIONS OF THE MARTINEZ FORMATION TO THE CHICO AND TEJON NORTH OF MOUNT DIABLO BY ROY E. DICKERSON. CONTENTS. PAGE Introduetion —.........----..-2.22-.-- DORE Soe a Tee tae So ee ie th nd A ein 17] Nature of Chico, Martinez, and Tejon Formations in the Area Con- FSlGG eX =X b caegeles iia rye On ary Done Bae OO a Sem eo Se he) eek es mente 172 Relation of Martinez to Tejon —............ Bae eee eesna pe aes es ar ee een ese ate 174 Vela pvO me ote War bimeZ scOm ONMCO) eesscssse-csc sen eeeescceac:ecsesee= foes esecee-:eeeeceeyececeeeeceeece 176 INTRODUCTION. The Martinez formation was first described by Gabb' from beds supposed to be transitional between the Chico and Tejon groups. It was shown later by Stanton? to contain a fauna dis- tinct from that of the Chico, but was referred by Stanton to the Tejon as a division of that group. In a study of the type loeality for the Martinez group Merriam® came to the conclusion 1Gabb, W. M., Rep. Geol. Surv. of Cal., Palaeontology, vol. II, p. 13, op. preface, 1869. 2 Stanton, T. W., The Faunal Relations of the Eocene and Upper Creta- ceous on the Pacific Coast, 17th Rep. U. 8. Geol. Surv., pp. 1011-1060, 1895-96. 3 Merriam, J. C., The Geologic Relations of the Martinez Group of Cali- fornia at the Typical Locality, Jour. of Geol., vol. 5, pp. 767-775, 1897. 172 University of California Publications. | GEOLOGY that the sharp separation of the Martinez fauna from that of the Chico and Tejon indicated that an unconformity certainly existed between the Martinez and Chico, and that sedimentation might have been interrupted between the times of deposition of the Martinez and the Tejon. In the work on the Martinez formation carried on in past + no locality was years by Gabb, Stanton, Merriam, and Weaver, found at which the stratigraphic relations of this formation to the Chico and Tejon were clearly shown. During the fall term of 1910, while working under the direc- tion of Dr. Merriam, in a small area four miles north of Mt. Diablo, the writer has been fortunate enough to find a section in which the Martinez-Chico and Martinez-Tejon contacts are well exposed, and the Martinez seems clearly separated by un- conformity from both the Chico and the Tejon. While this condition may be only local, it is interesting to find evidence of considerable time-intervals both preceding and following the deposition of the Martinez. The faunal relations between the Chico and the Martinez also illustrate strikingly the interruption of sedimentation. NATURE OF CHICO, MARTINEZ, AND TEJON FORMATIONS IN THE AREA CONSIDERED. The Chico formation in this region consists of a hard, dark, fine-grained sandstone with subordinate strata of dark gray limestone, which is interbedded with a shale and a soft buff sand- stone containing numerous fragments of leaves and stems. It has a general east and west strike and dip of 60°-70° N, and contains a characteristic Chico fauna including Meekia sella, Tnoceramus, sp., Venus varians, Mytilus, sp. (near quadratus), Tellina mathewsont, Pugnellus manubriatus, Cinulia obliqua, Helicoceras vermicularis, Ancyloceras, sp. The Martinez comprises a blue-gray, glauconitic sandstone and a sandy shale with thin strata of limestone. It has a general east and west strike and a dip varying from 35°-50° N. The 4+ Weaver, C. E., Contribution to the Palaeontology of the Martinez Group, Univ. Calif. Publ. Bull. Dept. Geol., vol. 4, pp. 101-123, 1905. Vou. 6] Dickerson: Martinez Formation. 1 ~l oe fauna of this bed is represented by numerous well-preserved specimens. The following lst of species corresponds closely to the fauna of the Martinez at the type locality. MARTINEZ FAUNA NORTH OF MT. DIABLO. Chico Martine Tejon Flabellum remondianum i * Trococyathus zitteli ey Cidaris, sp.(?) : _ Vv Anatina tyroniana (2) - Vv Cardium coopert SO i ee + a Crassatella unioides a 7 a Cucullaea mathewsoni AS Leda alaeformis a Leda gabbi | . # * Lima (?) multiradiata a Lima (?) n. sp. V Lucina (2) n.sp. Vv Mactra (?) n. sp. V Nucula truncata = i Pholadomya nasuta igs Pectunculus veatchii, var. major ee = ia Tapes quadrata He Tellina horni es a Tellina undulif era a Teredo, sp. Vv Zirphaea, sp. Vv Nucula, sp. = 7 5 V Ampullina striata "ua Anchura, n. sp. (a) Vv Anchura, n. sp. (b) : Vv Brachysphingus liratus 2 <= * : * Common. 7 Rare. ** Characteristic, V Unfixed, 174 University of California Publications. | GEOLOGY MARTINEZ FAUNA NORTH OF MT. DIABLO. Chico Martinez Tejon Cylichna costata 4 = Md Dentalium cooperi 7 a. = j 2 7 " Duscoheliz, sp. - Za ; _ ayy: zi a - Fusus, n. sp. ( 2) <= a Vv -—- - Galerus excentricus ss (ti(‘ et;*;*~*~*~;~;CS * -- Heteroderma, sp. ee a = _ ~ Lunatia horni: —vanll ain o 9 a. 7 +(%) 7 ~ Neptunea mucronata” 1 pean > ‘Perissolax tricarnatus =>) ee — Turritella infragranulata — Oo ae = Purritella pachecoensis BS + SC Urosyca caudata Siphonalia lineata Surcula, n.sp. (a) usa Surcula, u.sp. (dD) * Common. 7 Rare. ** Characteristic. V Unfixed. The Tejon is composed of white to dull red sandstone, coal strata in soft shales and sandstones, and a basal conglomerate, with a general east-west strike and a dip of 25°-385° N. Unio (?) penultimus and a leaf of a palm were found in the coal strata. Amauropsis alveata, Trocosmilia striata, Morio tuberculatus, Tapes conradiana, and Turritella weasana, were found above the coal strata in white sandstone. RELATION OF MARTINEZ TO TEJON. The evidence of relationship of the Martinez to the Tejon formation is based (1) upon areal mapping of the beds contain- ing characteristic faunas of these formations; (2) upon variation of strike at the contact of these formations; (3) upon variation in dip throughout the area studied; (4) upon the presence of a conglomerate which marks a very decided change in sedimenta- tion at the base of the Tejon. ~l oo) VoL. 6] Dickerson: Martinez Formation. ] The Martinez formation is represented areally by a strip averaging one quarter of a mile wide which extends from lower Oil Creek westward for four miles. Its west end is terminated by a eross-fault, while its eastern end is cut off by the Tejon conglomerate. Throughout the area studied there is a constant difference in strike between the Martinez and the Tejon. This is generally at least ten degrees, and in lower Oil Canon it is much greater. This difference in strike causes the Tejon conglomerate to rest upon a stratum of hard Martinez sandstone at one locality and upon soft Martinez shales at another, which sufficiently accounts for a very irregular Martinez-Tejon contact. In lower Oil Canon, a mile southeast of Stewartville, a basal conglomerate of the Tejon formation has a strike of N 45° W, while only a hundred feet away Martinez sandstone is found with a strike of N90° W. There ean be no doubt about the age of the sand- stone as it contained the following characteristic species at this loeality: Heteroderma, sp., Trococyathus zitteli, Tellina undult- fera, Urosyca caudata, Pectunculus veatchi, var. major, Nep- tunea mucronata. Professor Louderback, who has worked extensively in the Mt. Diablo quadrangle, has found Tejon fossils in the sandstone a few feet above and conformable with the conglomerate, so that the age of the conglomerate is certainly Tejon. The dip of the Martinez throughout the field is greater than that of the Tejon. The basal Tejon conglomerate, which is from ten to twenty feet thick, rests upon the Martinez sandstones and shales and forms a well-defined bed for over four miles in length. It consists of very coarse pebbles and boulders, which make it easily separable from the sandstones of the Martinez. The pebbles and boulders are in most places quartzose, but fragments of fossiliferous limestone, and sandstone and igneous rocks of various kinds also occur. Nucula truncata, Cylichna costata, Modiola cylindrica (2), Dentalium cooperi, and Zirphaca (2) bored boulders which resemble very closely the Zirphaea(?) borings on the Martinez-Chico contact described below, have been obtained from limestone and sandstone boulders imbedded in the 176 University of California Publications. | GEOLOGY conglomerate. Either the Chico or Martinez formations sup- pled this material, or possibly both may have contributed to this basal Tejon, as these species are limited to the upper Cretaceous and the Eocene on this coast. RELATION OF MARTINEZ TO CHICO. The evidence of relationship of the Martinez to the Chico is based (1) upon the areal mapping of the beds containing char- acteristic faunas of these two formations; (2) upon the variation of dip and strike at the contact; (3) upon a pre-Martinez fault in the Chico; (4) upon a sudden and complete change from Chico to Martinez fauna at he contact; (5) upon the presence of a line of boring molluses (Zirphaea) (2?) which have pene- trated the Chico alone the line of contact. The strike of the Chico and Martinez throughout most of this field is approximately the same. One marked variation occurs in lower Oil Canon, where the strike of the Chico is N 75° W, while that of the Martinez which rests upon it is N90° W. } Towa,’’ and in the Hay Springs deposits on the Niobrara River, Nebraska, all of which are of Pleistocene age. In 1902" Matthew described an animal from the Hay Springs fossil beds mentioned above, which appeared to be related to Merycodus and to Antilocapra. This form he named Capromeryx furcifer, referring it to the Merycodontidae. Neotragocerus inprovisus,” described by Matthew and Cook from the Snake River formation of western Nebraska, repre- sents the existing Kurasian and African tragocerine division of the antelopes. American representatives of the strepsicerine or twisted- horned group of antelopes were recently discovered by J. C. Merriam® in the Thousand Creek beds of northern Nevada and deseribed as Ilingoceros alexrandrac. Sphenophalos nevadanus, found with Ilingoceros, while ‘‘not far removed from the tragela- phine forms of the Thousand Creek fauna,’’ is not clearly referable to any of the existing subdivisions of antelopes. The fossil material representative of antelopes in North America being so exceedingly seanty, additional interest attaches to each new fragment. DESCRIPTION CAPROMERYX(?) MINOR, new species Jaw very much smaller than that of Jaws and Dentition. Antilocapra americana of shghtly greater age. The specimen of prong-horn at hand (no. 8299, Calf. Mus. Vert. Zool.) still retains the milk dentition, but its molars are further advanced than in Capromeryx. The length of one of the portions of the jaw of Capromeryx(?) minor (no. 12523) is 55mm.; while a roughly corresponding one of Antilocapra americana is 170 mm. The dimensions indicate that the present species is about the same size relative to the size of the prong-horn as is Capro- 1 Bull. Am. Mus. Nat. Hist., vol. 16, 1902, p. 317. 2 Bull. Am. Mus. Nat. Hist., vol. 26, 1909, pp. 361-414. 38 Univ. Calif. Publ. Bull. Dept. Geol., vol. 5, p. 320, 1909. 1911] Taylor: A New Antelope from Rancho La Brea. 193 meryx furcifer, which is said to be two-thirds the size of Antilo- capra. Milk P, of the new form is primitive, resembling P, of Merycodus in that the anterior valley of its inner surface is entirely open toward the inner side, but more advanced than Merycodus in that the posterior valley is closed. This may indicate an advance in specialization, but it is difficult to say definitely, since milk and permanent teeth are the ones com- pared. The degree of hypsodonty of the teeth is like that of Antilocapra, being far in advance of Merycodus. Figs. la to 2b.—Capromeryx (?) minor, new species. Rancho La Brea, near Los Angeles, California. Figs. la, 1b, and 1e. aspect; 1b, superior aspect; lc, external aspect. Jaw, no. 125238, natural size. Fig. la, internal Figs. 2a and 46.—Jaw, no. 12817, natural size. Fig. 2a, internal aspect; 2b, external aspect. Metapodials—The metapodials approach the antilocaprine type in the following characters. The anterior groove in the 194 University of California Publications in Geology. (Vou. 6 posterior metapodial has approximately the same relative posi- tion as in the prong-horn, being slightly more median than is the ease in the Cervidae. This groove is emphasized to about the same degree in C.(?) minor as in Antilocapra americana, being very shallow for the middle part of its length. The fossa ex- ternal to the proximal end of the median anterior groove is pro- nounced, as in the prong-horn. The posterior median groove, while in general lke that in Antilocapra, is wider. seas eee re ae ete oe ee Arctomys nevadensis Kellogg Anctomiys mim ors Keelll 0p! 0 teaser taccssneetatsese stares eee eee CUM US Spe 22 ec was ee tas ess seus ap cesetent sepeseeenses Sapoeee even ste 253 Asplodomtud vey Sezer reecesteseasse sence ste veneeeee fee e ee senaee eeeeaes nee ee 254 Aplodontia alexandrae Furlong ............--..--..------20----20ceesee-seeeeeeeeee 254 Miylaip anil ae: 2c orosoce soca s ae ccce cst eceedc en sneececbnsc test caneescee es 254 Mylagaulus momodom Cope; =e 22sec cece ccrcseceecce cocescue sense seer 254 Mylagaulus pristinus Douglass -....---.--..2-2..:..5-22-c-cceeeeceeeee eee 254 ROE HS Hoy CG Ec ee ein a nee Sr eli 254 Hucastor Veconter (Merriam (Ji C)) 2 ccsecccccecsececesseeseeesee sees ees 254 DIP OUMOS ek S ph Fi iieesasccer= eeecesc cree oe lashes reset hee ree 254 Gre OTM y Cae ys 2e ees ease aa cece oceans eee ee 254 Hntoptychus minimus Kellogg, ooo... scceciscccee ace ace ee cee cee 254 KO Gach =} so: - aro eE y o PPP P Per Breer ere rater, 255 Peromiyscus antiquius: Kellio oo in ' Issued October 9, 1911 rc : . BY LOYE HOLMES MILLER | J hs BERKELEY “THE UNIVERSITY yRES™, The ‘Unicon of California Publi ations ‘are 0 red. n : cations of learned Societies and institutions, universities and libra all the publications df the University will be sent upon request.. F\ i publications and other information, address the Manager of the er en California, U. S. A. All matter sent in exchange should A addreseedy wis Department, University Library, Berkeley, California, U. S. : Oro HaRRAssow11z R. FRIEDLAENDER & 0: H LEIPZIG . BERLIN Agent for the series in American Arch- Agent for the series in Ameri aeology and Ethnology, Classical Philology, aeology and Ethnology, Botany, Edueation, Modern Philology, nex Mathematics, Pathology, — Ph Psychology. Zoology, and Memoirs. Geology.—ANbREW C. Lawson and Jouwn C. Merriam, Editors. Price per volume Volumes I (pp. 428), IL (pp. 450), III (pp. 475), IV (pp. 462), Vv ee ee _ completed. Volume VI (in progress). Cited as Univ. Calif. Publ. Bull. Dept. Geol. VOLUME 1. — 1. The Geology of Carmelo Bay, by Andrew C. Lawson, with chemical analyses cooperation in the field by Juan de la -C. Posada 2. The Soda-Rhyolite North of Berkeley, by Charles Palache............... sa ESM _ 3. The Eruptive Rocks of, Point Bonita, by F. Leslie Ransome............. 4. The Post-Pliocene Diastrophism of tle Coast of Southern California, by Andrew ©. Dawson. is 22S eae Se A es a 5. The Lherzolite-Serpentine and Associated Rocks of the Potrero, San ‘Francisco, | \ Charles Palache. 5 6. On a Rock, from the Vicinity of Berkeley, containing a New Soda Anpetalae b Charles Palache. ~ Nos:,'5 and 6 4in Yone .cover.2 0s ioe ie Ses ee ee 7. The Geology of Angel Island, by F. Leslie Ransome, with a Note on the Radiola y Chert from Angel Island and from Buri-buri Ridge, San Mateo County, California by (George! Jennings “Hinde, Vj.i0 3 oe ee 8. The Geomorphogeny of the Coast of Northern California, by Andrew C. = 5; 9, On Analcite Diabase from San Louis Obispo County, eaiteey aby by Heel Ww. MAT DATES: 02 ES ey NT ae AS eh cee, he RS Sa ec 2 2 10. On Lawsonite, a New Rock-forming Mineral from the Tiburon Peninsula, County, California, by F. Leslie: Ransome-i:.-.2 20.25. fee See 11. Critical Periods in the History of the Earth, by Joseph LeConte.........220.-- 12. On Malignite, a Family of Basic, Plutonic, Orthoclase Rocks, Rich in pegs an Lime, Intrusive in the Coutehiching Schists of Poohbah take C. Lawson * adieonpiticeegg ci Gk 2S a 13. Sigmogomphius LeContei, a New Castoroid Rodent, from .the es ae | Berkeley,’ by John C. Merriam: /00 2S ee a 14. The Great Valley of California, a Criticism of the Theory of Isostasy, Leslie Ramsome -.....---2-.-2---2c2c ec teececc een ccecteececeee cee cec cent teeenecececennenenemanenersensneneneaseannen VOLUME 2. 1. The Geology of Point Sal; by Harold Wy Fairbanks... Mea ees we On Some Pliocene Ostracoda from near Berkeley, by Frederick Chapman. 8. Note on Two Tertiary Faunas from the Rocks of the Southern Coast of Vancot Mslamd,” biy ei.) Clery ria soo ae ae ee ee oe oe eee 4. The Distribution of the Neocene Sea-urchins of Middle California, and Its Bea: on the Classification of the Neocene eee by John C. Merriam Be . A Contribution to the Geology of the John Day Basin, by John C. Merri Mineralogical Notes, by Arthur S. Hakle_.....-----.-.-2.-.-1---1cseseseceestece eee Ses . Contributions to the Mineralogy of California, by Walter C. : 12. The Berkeley Hills. A Detail of Coast panes ie by Andrew @hairles!, Paliiehre i225 5 tee aes ae ee gene Peseestetieescsncnnscces UNIVERSITY OF CALIFORNIA PUBLICATIONS BULLETIN OF THE DEPARTMENT OF GEOLOGY Vol. 6, No. 12, pp. 305-316 Issued October 9, 1911 A SERIES OF EAGLE TARSI FROM THE PLEISTOCENE OF RANCHO LA BREA BY LOYE HOLMES MILLER CONTENTS HERE CXS ECO 0 nc FIDE: S CTE UTC MMO Tm S10 CCC Sa ere se ees ee eae RE ae : Pxquimlamchrysactos (Liamnaeus))) 202-222. 2-cecc ec eee cc eee eee seco detecenceceeceeetenee ae Haliaétus leucocephalus (Linnaeus) Morphnus woodward, n. Sp. ......22.-2-.22::--:--cceeceeeeeceeeceeeeeeseeeeceseeeceeeeeoeeeeees 312 Geranoaétus grinnelli, n. Sp. -....2.-.--------nceececceceeeceeceeceeeececseeneenceceseeeneeeeesees 314 Gemamoaetusetragilign@n: iS ps cores ee ccc cece rece sce once eee cada fose ee eet deeseven 35 Comparative Table of Measurements of the Series —.....-2...22.22.2220.00020--2----- 316 INTRODUCTION Attention has already been called to the fact that the condi- tions under which the Rancho La Brea birds were entrapped and preserved were especially conducive to the preservation of the tarsometatarsus.t. This bone is so characteristic a part of the avian skeleton and reflects so readily the characters of the species that in discussing a large amount of material, such as that assembled in the University of California collections, there should be no hesitation in asserting the identity of the specimen to be considered when based on the characters of the tarsometa- tarsus. The above principle is especially true of the Acciptres, a group in which the tarsometatarsus is even more distinctive than is the raptorial beak. 1 Miller, L. H., Univ. Calif. Publ. Bull. Dept. Geol., vol. 6, p. 1, 1910. 306 University of California Publications. | GroLogy The present discussion includes all the buteonid material per- taining to species that were evidently larger than Archibuteo ferrugineus. This material forms a series of sixty almost perfect tarsometatarsi. The slight imperfections consist in the main of fractures only, there being almost no corrosion. The surface of the bone is as smooth as in newly macerated specimens and assumes, in cleaning, a beautiful polish with every rugosity and every intermuscular line perfectly distinct. Four specimens of Recent American eagles are at. hand for comparison. Aquila is represented by one specimen, a large bird fully adult. Haliaétus is represented by an individual taken at Long Island, N. Y., which belongs to the variety lewcocephalus, and also by a speci- men of the Alaskan race alascanus, a large female in the collec- tion of the California Museum of Vertebrate Zoology. The peculiar long-shanked group of South American eagles is repre- sented by a single specimen of Geranoaétus melanoleucus, an adult individual of unknown sex. Various smaller American buteonids are at hand, also four Old World forms from the genera Otogyps, Neophron, Circaétus and Gypaetus. Besides the actual specimens named, two casts were available for comparison. These casts were made through the courtesy of Dr. A. Smith-Woodward and represent the tarsometatarsi of Thrasaétus harpya and Morphnus guianensis. They are casts of specimens in the British Museum of Natural History. It is a pleasure here to acknowledge the service rendered by Dr. Smith- Woodward. The fossil specimens fall easily into five distinct series, each of which shows a remarkable degree of homogeneity, and each of which unquestionably represents a form specifically distinct. Most of the series are large enough to include all individual varia- tions that could reasonably be expected to occur in the limits of a species as the result of varying age, sex, or individuality. The two largest of these series represent the existing Sonoran species Aquila chrysaétos and Haliaétus leucocephalus. Since, however, a detailed discussion of the tarsometatarsus of these forms was not discovered in the literature upon attacking the present prob- lem, it is hoped that a comparison of the two forms here will not prove superfluous. 1911] Miller: Eagle Tarsi from Rancho La Brea. 307 DESCRIPTION OF SPECIES AQUILA CHRYSA#TOS (Linnaeus) Twenty-nine almost perfect tarsi represent this existing species. Except in the matter of size there is almost no per- ceptible variation in the specimens of the entire series. A greater or less distinctness in the rugosities about the head of the bone to which the articular ligaments attach is here ascribed to age of the individual. The positions of these rugosities are very constant and form one of the bases of distinction between the genera Aquila and Haliaétus. Differences in size of the two extremes of the series are quite noticeable; there is, however, a complete intergradation in this respect. This variation is, in all probability, due to sex and individuality combined, large males intergrading with the smaller females in regard to size of tarso- metatarsus. The most noticeable differences between this series and the Haliaétus series lie in the characters of the head region of the bone. When viewed from the front, the depression into which the two proximal foramina open is deep and sharply delineated on all sides except the distal side. The inner margin of this depression just even with or but slightly above the internal, proximal foramen is marked by an elongate, ridge-like papilla which is the outer attachment of the ligamentous supratendinal bridge. In the genus Haliaétus, the proximal depression is very shallow and ill defined and the outer attachment of the ligamentous bridge lies almost directly above the interior proximal foramen. The tubercle of the tibialis anticus is much the same except that it is placed further down the shaft in Aquila. On viewing the bones from their proximal articular faces, the two species are at once distinguishable by the much greater development in Aquila of the outer ridge of the hypotarsus. In Haliaétus this portion appears as a rounded hillock, whereas in Aquila it is developed into a strong unciform process. Minor differences lie in the positions of the proximal foramina. These are placed close together in Haliaétus and the outer is almost invariably raised appreciably above the inner. The reverse is true of the foramina in Aquila. In the latter genus the inner attachment of the ligamentous bridge is usually less distinct and less elongate than in the former. The length of the bone in Aquila averages greater and the robustness less. The inner trochlea is larger in every respect, the outer trochlea is more com- pressed laterally. None of the bones in the large series of Aquila surpasses in size the single specimen of the Recent phase which is at hand. The evidence furnished by the group of fossil tarsometatarsi is 308 University of California Publications. [ GEOLOGY such as to indicate that Aquila chrysaétos was abundant and probably the dominant eagle of the region during the Pleisto- cene, and that it has remained till the present time practically unchanged. Figs. la to 5b. The anterior faces and the proximal articular surfaces of the tarsometatarsi. All figures natural size. From the Pleistocene of Rancho La Brea. Figs. la-1b. Aquila chrysaétos (Linnaeus). No. 12788. Figs. 2a-2b. Haliaétus leucocephalus (Linnaeus). No. 12789. Fig. 3a. Morphnus woodwardi, n. sp. No. 12787. Fig. 4a. Geranoaétus grinnelli, n. sp. No. 12175. Fig. 5a. Geranoaétus fragilis, n. sp. No, 12757. 1911] Miller: Eagle Tarsi from Rancho La Brea. 309 Mention has been made of the occurrence in the asphalt of A survey of the entire collection large numbers of this species.” of birds in the collections of the Department of Palaeontology at the University shows it to outnumber by 100 per cent any other POSE Eee 2 am tke A on. dys, All figures Anterior faces of tarsometatarsi. Figs. 3b to 5b. From the Pleistocene of Rancho La Brea. No. 12787. size. Fig. 3b. Morphnus woodwardi, n. sp. Fig. 4b. Geranoaétus grinnelli, n. sp. No. 12175 Fig. 5b. Geranoaétus fragilis, n. sp. No. 12757. 1909. natural 2 Miller, L. H., Univ. Calif. Publ., Bull. Dept. Geol., vol. 5, pp. 305-317, 310 University of California Publications. | GEOLOGY species represented. Despite the fact that eagles are known to resort to carrion diet at times, the great preponderance of this bird’s remains over those of other avian species is surprising. Was the golden eagle numerically so much more abundant than any of the vultures as to have outnumbered all species of that group despite its less habitual resort to carrion? Was its feeding upon earrion a matter of more common occurence then than now? 2 ah BECTON Issued October 28, 1911 OTES ON THE RELATIONSHIPS OF THE ’ BERGEN BY WIMAN ¥ JOHN C. MERRIAM “NOTES ON THE DENTITION. OF _ OMPHALOSAURUS - BY. % JOHN c . MERRIAM AND HAROLD C. BRYANT ee ee :. dongs i Me NOV: OTE Ne tional ose : BERKELEY THE UNIVERSITY PRESS | 2 te UNIVERSITY OF CALIFORNIA PUBLICATIONS ene Notr.—The University of. California Publications are offered in exch ny Department, University Library, Berkeley, California, U. S, A. Be Otto HARRASSOWITZ R. FRIEDLAENDER & SOHN ~ y LEIPZIG BERLIN Rs Agent for the series in American Arch- Agent for the series in America aeology and Ethnology, Classical Philology, aeology and Ethnology, Botany, Education, Modern Philology, Philosophy, Mathematics, Pathology, Psychology. Zoology, and Memoirs. Geology.—ANpDREW C.: Lawson and JoHN C. Merriam, Editors. Price per volume, $3.6 Volumes 1 (pp. 435), II (pp. 450), III (pp. 475), IV (pp. 462), V (pp. 448), ‘ completed. Volume VI (in progress). >. an Cited as Univ. Calif. Publ. Bull. Dept. Geol. Vol. 1, 1893-1896, 435 pp., with 18 plates, price $3.50. A list of the titles i this volume will be sent on request. VOLUME 2. 1. The Geology of Point’ Sal, by Harold W. Paitbanks.... 2) 26 2. On Some Pliocene Ostracoda from near Berkeley, by Frederick Chapman.... 3. Note on Two Tertiary Faunas from the Rocks of the Southern Coast of Vaneouv sland) iy. J.2 Oat Mie rr a Wiis tes essen eee een a cecaneea btn este . The Distribution of the Neocene Sea-urchins of Middle California, and Its Bearing on the Classification of the Neocéne Formations, by John‘C. Merriam................ 4 5. The Geology of Point Reyes Peninsula, by F. M. Andersofi.....-..-.---.-022-se-- eee 6. Some Aspects of Erosion in Relation to the Theory of the Peneplain, by W. Tampier.. Smith ) 22s on Sack eee Stee ed Pe rr 7. A Topographic Study of the Islands of Southern California, by W. S. Tangier Smith 8. The Geology of the Central Portion of the Isthmus of Panama, by Oscar H. Hershey 9. A Contribution to the Geology of the John Day Basin, by John C. Merriam... 10. Mineralogical Notes, by Arthur S. Hakle 11. Contributions to the Mineralogy of California, by Walter C. Blasdale. 12. The Berkeley Hills. A Detail of Coast Range Geology, by Andrew C. Lawson and © Charles “Palachte, .“sts....---22h ae te 2 a Se ee ee oe ee ee VOLUME 3. 1. The Quaternary of Southern California, by Oscar H. Hershey 22:-.2..---222.-2---sceeeeceeeeeeeneee 2. Colemanite “from Southern California, by Arthur 8. Hakle.._.c2. 2c i ‘3. The HEparchaean Interval. A Criticism of the use of the term Algonkian, by © Andrew C.-L wsony. soe see nn 4, Triassic Ichthyopterygia from California and Nevada, by John C. Merriam......... 6.-The Igneous Rocks near Pajaro, by John A. Reidse. a2. econo ce ctgencucec sree eee 7. Minerals from Leona Heights, Alameda Co., California, by Waldemar T. Schaller 8. Plumasite, an Oligoclase-Corundum Rock, near Spanish Peak, California, by Andrew C.> Lawson json ree a EPR OE RO cry cr 9. Palacheite’. by. Arthur .S:-Walde® 3-229. We, asd ee ee 10. Two New Species of Fossil Turtles from Oregon, by O. P. Hay. 11. A New Tortoise from the Auriferous Gravels of California, by W. J. Sinclair. Nos. 10 and-dl dn one" coverss... 25 205.202 erence eee ee ce : 12. New Ichthyosauria from the Upper Triassic of California, by John C. Merria 13. Spodumene from San Diego County, California, by Waldemar T. Schaller_._.... 14. The Pliocene and Quaternary Canidae of the Great Valley of California, b; Mohn » Cag Mle r reales 2-525 ae eal ee a ae 15. The Geomorphogeny of the Upper Kern Basin, by Andrew C. Lawson.. 16. A Note on the Fauna of the Lower Miocene in California, by John C. Merriam 17. The Orbicular Gabbro at Dehesa, San Diego County, California, by Andrew DG WWSOM: ees oa ceca ne cn cc oc cee cece Se eee eo a ne re a er a 18. A New Cestraciont Spine from the Lower Triassic of Idaho, by Herbert M. Kv 19. A Fossil Egg from Arizona, by Wm. Conger Morgan and Marion Clover Tall 20. Euceratherium, a. New Ungulate from the Quaternary Caves of California, by William J. Simelar amd) Hs 5 War ome eee ee, eee coer ge ee nets es 21. A New Marine Reptile from the Triassic of California, by John C. Merriam 22. The River Terraces of the Orleans Basin, California, by Oscar H. Hershey. UNIVERSITY OF CALIFORNIA PUBLICATIONS BULLETIN OF THE DEPARTMENT OF GEOLOGY Vol. 6, No. 13, pp. 317-327 Issued October 28, 1911 NOTES ON THE RELATIONSHIPS OF THE MARINE SAURIAN FAUNA DESCRIBED FROM THE TRIASSIC OF SPITZ- BERGEN BY WIMAN BY JOHN C. MERRIAM CONTENTS PAGE EVRTGSECOX TIVES KO Oc ae Se eC 317 © Cerra CC Came ema eee a TAME Serres hes gece ce leit 318 Mixosaurus(?) nordenskioldii (Hulke) 2220002200020 cee cece cece ene 318 Pessosaurus polaris (Hulke) 22222 cec cece cecee cee eececeeceeveceeceeeeeeeeeeee 323 JP COISISTOYONESEE6:5 See 324 Sennen — 1 g9 2) Waa) AAS) eof) eee up EC 326 INTRODUCTION Since Nordenskiold’s discovery of a number of fragmentary ichthyosaurian specimens in the Triassic of Spitzbergen in 1864 the hope has often been expressed that we might know more of the saurian fauna of this interesting region. Though additional material has been obtained from time to time,? it was not until recently that any considerable number of specimens was brought together for study. In 1908 and 1909 important collections were obtained at Spitzbergen by Carl Wiman and Bertil Hégbohm, making pos- 1 Hulke, I. W., Bih. till K. Vet. Akad. Handl. Bd. 1, No. 9. 1873. 2 Yakowlew, N., Verh. d. Russ. Kais. Min. Ges. St. Petersb. Ser. 2, Bd. 40, p. 179. 1902. 318 University of California Publications. [ GEOLOGY sible a more satisfactory determination of the nature of the saurian forms represented in this fauna than had previously been possible. The results of a study of the collection by Wiman* form a most interesting and important contribution to our knowl- edge of this group, and materially assist in comparison of the Spitzbergen Triassic with that of the rest of the world. OCCURRENCE The ichthyosaurian remains from Spitzbergen are described by Wiman as occurring in two horizons of the middle Trias. The upper horizon is in the Daonella shales, and contains abund- ant specimens of the ammonite genus Ptychites. The saurian collection from the upper beds comprises Mixrosaurus(?) norden- skioldu (Hulke), and Pessosaurus polaris (Hulke). The lower saurian horizon is about three hundred and fifty feet below the upper beds. Below it is an ammonite fauna in- eluding Ceratites polaris. At this horizon two saurian forms were found, which are described as Pessopteryx nisseri, n. gen. and sp., and P. minor. A short distance below the lower horizon a number of large ichthyosaur teeth were found. Excepting the specimens representing M.(?) nordenskioldu, all of the material from Spitzbergen unfortunately consists of seattered or isolated bones. The M.(?) nordenskioldi specimens are much better preserved than the others, and in some eases show considerable connected parts of skeletons, MIXOSAURUS(?) NORDENSKIOLDII (Hulke) Both Mixrosaurus(?) nordenskioldii and Pessosaurus polaris were first described by Hulke in 1873 under the name of Ichthyo- ° saurus. Since that time it has been clear to several writers that they could not remain in that genus, and various suggestions as to their possible relationships have been made by Dames,* Yakowlew,°® and Merriam.° 3 Wiman, Carl, Ichthyosaurier aus der Trias Spitzbergens, Bull. Geol. Inst. Upsala, vol. 10, pp. 124-148. 1910. + Dames, W., Sitzb. d. Acad. d. Wiss. Berlin, 1895, p. 1045. 5 Yakowlew, N., Verh. d. Kais. Russ. Min. Ges. Bd. 40, p. 179. 1902. 6 Merriam, J. C., Univ. Calif. Publ. Bull. Dept. Geol. vol. 3, pp. 87, 88. 1902. 1911] Merriam: Saurian Fauna of Spitzbergen. 319 Wiman’s studies of M.(?) nordenskioldii make possible for the first time a fairly satisfactory suggestion as to the affinities of this form. From a study of the excellently preserved material of this species Wiman has been able to show the close similarity of this form to Mixosaurus cornalianus from the Besano beds of northern Italy, and also to the imperfectly known Cymbospon- dylus(?) natans from the Middle Triassic of the West Humboldt Range in Nevada. Fig. 1. Mixosaurus(?) nordenskioldii (Hulke). A portion of the lower jaw with dentition. Natural size. (After Wiman). Fig. 2. Mixosaurus(?) nordenskioldii (Hulke). Upper jaw fragment . with dentition. Natural size. (After Wiman). The skull of M.(?) nordenskioldti is known only by a few fragments. Fortunately in many instances these pieces bear teeth, so that some important characteristics of the dentition appear. As was shown by Dames, the dentition is thoroughly differentiated. The posterior teeth are low, laterally-compressed domes, the anterior teeth are small, approximately conical, and round in cross-section. The roots are coarsely folded as in the 320 University of California Publications. [ GEOLOGY specimens of J/.(?) atavus deseribed by Fraas,’ from the middle Trias of Germany, and are set in more or less distinctly separ- ated alveoles. The dentition in several specimens, as appears in figure one adapted from Wiman, is very close to that of Phalaro- don, a Nevada Middle Triassic form recently described* by the writer. The teeth of other specimens (fig. 2) are less lke Phalarodon and more like Mirosaurus of the Italian Triassic. It seems not impossible that two types are represented in Wiman’s material. One of the most inter- esting discoveries made by Wiman is the finding of ex- cellent material represent- ing the limbs and arches of M.(?) nordenskioldu. Both anterior and __ posterior limbs were obtained in such excellent state of preser- vation that nearly all the essential characters can be determined. In both limbs the epipodial elements are distinctly elongated and separated by a median cleft as in most Triassic ichthyo- saurs, and the phalangeal elements generally show the median constriction, which has been considered -as representing a rudimen- tary shaft region. The anterior limb (fig. 3) is in general much like that of Mixosaurus cor- Fig. 3. Mirosaurus(?) nordenskioldii : ‘ (Hulke). Anterior limb, X 24. R, radius, “@ltanus of the Italian (After Wiman). Triassic. It differs from 7 Fraas, E., Ichthyosaurier der Stiddeutschen Trias-und-Jura-Ablagerun- gen, 1891, p. 38; Taf. 1, figs. 17 and 18, and Taf. 3, figs. 2 and 3. 8 Univ. Calif. Publ. Bull. Dept. Geol. vol. 5, p. 382. 1910. 1911] Merriam: Saurian Fauna of Spitzbergen. 321 the Italian specimens thus far described in possessing a sixth digit. The first three segments of the anterior limbs are prac- tically identical with those of Cymbospondylus(?) natans, a Mixosaurus-like species from the Middle Triassic of Nevada. The posterior limb (fig. 4) is almost identical in form with that of Mixosaurus cornalianus, even to the duplication of a peculiar arrangement of the proximal carpals found in the Italian species. Fig. 4. Mixvosaurus(?) nordenskioldii (Hulke). Pelvie arch and_ pos- terior limb, X 4%. P, pubis; I, ischium. (After Wiman.) The pelvic arch (fig. 4) is almost identical with that in most specimens of the American Cymbospondylus, and differs from that of Mirosauwrus in the absence of an obturator foramen in the pubis. The pectoral arch is like that of Mirosaurus excepting in the form of the interclavicle, which has a remarkably wide trian- gular form with a distinct reéntrant angle on the anterior side. The complete vertebral column is not known, but fortunately considerable numbers of vertebrae, including the posterior dorsal region and a large part of the tail, were found in a continuous series (fig. 5). As in Mirosaurus cornalianus, the tail makes a gentle upward curve near the middle and droops slightly at the posterior end. In the Spitzbergen form as represented in the specimen figured by Wiman the upward curve is much nearer the dorsal region than in M. cornalianus; in contrast to Cymbos- pondylus, in which the curve is farther back than in the Italian species. 322 University of California Publications. [GEOLOGY The posterior dorsal and the caudal vertebrae are character- ized by very high, slender neural arches. The arches stand nearly erect over the posterior dorsal and anterior caudal regions, but are suddenly turned sharply forward near the middle of the \\ gna < Fig. 5. Mixosaurus(?) nordenskiolditi (Hulke). * - ’ 7 i! UNIVERSITY OF CALIFORNIA PUBLICATIONS BULLETIN OF THE DEPARTMENT OF GEOLOGY Vol. 6, No. 14, pp. 329-332 Issued October 28, 1911 NOTES ON THE DENTITION OF OMPHALOSAURUS BY JOHN C. MERRIAM anp HAROLD C. BRYANT INTRODUCTION In the saurian collections which have been obtained in the marine Middle Triassic of Nevada during the last ten years a number of specimens have appeared which represent a form apparently differing from all known reptilian types. os P % Fe o id > 7 BERKELEY | _ THE UNIVERSITY PRESS. - 16. A Note on the Fauna of the Lower Miocene in California, by John C. Merriam en : Saber Nore.—The University of California Publications’: e cations of learned societies and institutions, universities and abs all the publications of the University will be sent upon request. publications and other information, address the Manager of the Universi California, U. S. A. All matter sent in exchange should be addresued to Department, University Library, Berkeley, California, U. S. A. — a a Pi OTTO HARRASSOWITZ _ BR. FRIEDLAENDER & § LEIPZIG BERLIN Agent for the series in American Arch: Agent for the series in Ame aeology and Ethnology, Classical Philology, acology and Ethnology, Botany Education, Modern Philology, Philosophy, Mathematics, Pathology, Psychology. Zoology, and Memoirs. Geology.—Anvrew C. Lawson and Joun C. MerRiAM, Editors. Price per volume, $ Volumes 1 (pp. 435), IL (pp. 450), IIL (pp. 475), IV (pp. 462), V (pp. 448), completed. Volume VI (in progress). in Cited as Uniy. Calif. Publ. Bull. Dept. Geol. A «fs ye” “Vol. 1, 1893-1896, 435 pp., with 18 plates, price $3.50. A list of the titles 5 this volume will be sent on request. VOLUME 2. 1. The Geology of Point Sal, by Harold W. Pairbanks.........-..---ccee-c-ccceee-neeeeeeeeeeees 2. On Some Pliocene Ostracoda from near Berkeley, by Frederick Chapman........ 3. Note on Two Tertiary Faunas from the Rocks of the Southern Coast of Vancouy Island: by “J... Ci oMerriam: 2.0.0 220 notin a eee ame 4. The Distribution of the Neocene Sea-urchins of Middle California, and Its Bearing © = 5 6 on the Classification of the Neocene Formations, by John C. Merriam... . The Geology of Point Reyes Peninsula, by F. M. Anderson...) 9s eee . Some Aspects of Erosion in Relation to the Theory of the Peneplain, by W. Tangier” Smith. s.0.20.2 ee ee 7. A Topographie Study of the Islands of Southern California, by W. S. Tangier Smi 8. The Geology of the Central Portion of the Isthmus of Panama, by Oscar H. Hershey 9. A Contribution to the Geology of the‘John Day Basin, by John C. Merriam.. 10; Mineralogical. Notes, by Arthun S Hakle..... 22. eee 11. Contributions to the Mineralogy of California, by Walter C. Blasdale......... 12. The Berkeley Hills. A Detail of Coast Range Geology, by Andrew C. Lawson and Charles: Palachee © 2222... ci2.csi2s.c Amide w -C. Lawson» se.c205-2pecsece tse ater cas So- natn toae aaeennt oop oe ec neon 4, Triassic Ichthyopterygia from California and Nevada, by John C, Merriam 6. The Igneous Rocks near Pajaro, by—Jiohn: A. eid... 2 cso oe soe eee 7. Minerals from Leona Heights, Alameda Co., California, by Waldemar T. Seha 8. Plumasite, an Oligoclase-Corundum Rock, near Spanish Peal, California, b Andrew ©. Lawson -2..2--.--.--c2-----s 9. Palacheite, by Arthur S. Hakle 0. Two New "Species of Fossil Turtles from Oregon, by O. P. Hay... 1. A New Tortoise from the Auriferous Gravels of California, by W. J. Sinelain Wos: 10 andsil invone-cover-:s2.-2. eee oleae anes 12. New Ichthyosauria from the Upper Triassie of California, by John C. Merriam. 18. Spodumene from San Diego County, California, by Waldemar T. Schaller... 14. The Pliocene and Quaternary Canidae of the Great Valley of Californ a Sion Cee were aah a a ca ne a 15, The Geomorphogeny of the Upper Kern Basin, by Andrew C. Lawson. 17. The Orbicular Gabbro at Dehesa, San Diego County, Caiifornia, by Andrew MER WSO oo oke ae cece dace aa ceo 2g ee 18. A New Cestraciont Spine from the Lower Triassie of Idaho, by Herbert M 19, A Fossil Egg from Arizona, by Wm. Conger Morgan and Marion Clover 20. Euceratherium, a New Ungulate from the Quaternary Caves of Califor . William J. Sinclair and E. L. Furlong. .-n...nn.---2- ce c-2-2c2cecseccnecneeerenenennnnenernaennee 21, A New Marine Reptile from the Triassic of California, by John C, Merriam 22. The River Terraces of the Orleans Basin, Sa by Oscar H. Hetshey. UNIVERSITY OF CALIFORNIA PUBLICATIONS BULLETIN OF THE DEPARTMENT OF GEOLOGY Vol. 6, No. 15, pp. 333-383, pls. 34-43 Issued December 2, 1911 NOTES ON THE LATER CENOZOIC HISTORY OF THE MOHAVE DESERT REGION IN SOUTHEASTERN CALIFORNIA BY CHARLES LAURENCE BAKER CONTENTS PAGE SOE UCLA NO a pee 334 Location and Boundaries of the Mohave Desert ~................0.2-:2----0ec--eeeees 335 Metamorphic, Plutonic, and Voleanic Rocks older than the Upper IO Cee ree ween ree a ick on es ures eer ee ates Delis tide 336 The Oro Grande Series ~........2...2..22::2:--000--- Bsns Reteeeen ee S823! Rete SP Deoe vrs 336 Basement Rocks of the San Bernardino Range ...................-2..2-1.-2-------4 337 Granitic Bedrock of the Mohave Desert and Contiguous Ranges ...... 338 Lavas Perhaps Earlier in Age than Upper Miocene .................-.-.------- 338 The Rosamond Series of Upper Miocene Age ...........22.2..2.22:2:200200edeeeeeeeeeees 339 Definition and Distribution of the Series —.....222222..00..ceeeeee eee 339 Rosamond Exposure North of Barstow ~............222.2..220.2.220-2220020-200-0e2- 342 Basal@brecciae: Member se. 42.2200: c.cees cecccenxbececacedt cccptcatsedasuctespeeercctcne 342 Manti-breceia Member ....2.2-...-.2.2e:e-ccc2-cececceecsegeeeececencnceeesecvcueeceesecesecdleee 342 Fine Ashy and Shaly Tuff Member _...022202202022ceeeeee eee 343 Resistant Breccia Member .............---2:-:c-:ccccceecececceeceeceeseeecececeeeceeceeees 344 Mossulaterous) Mutt “Member <2..2c:.c--c-cccccccb2e<2-c0ceeceeteececeneceuceeerenteceeene-cee 345 Structure of the Rosamond Series in the Barstow Locality .......... 346 The Black Mountain Rosamond Exposure ................22..2.220.22-202002000000--+ 347 Mfc DTECCIA PMCID OLY ie. 2 2. ccs: ce. pescct casenccthecssesdeci cet caneccbvtaccgechactstctecstesas 347 Fine Ashy and Shaly Tuff Member ...............2..2-.2202-2---eeeeeeeeeeeeeenq- B47 Upper Member of Breccia and Tuff ~.2.....2202.0..2222.ccetceeeeeeeee cece 348 Structure of the Rosamond at Black Mountain —....000000200000000-..- 348 Rosamond Beds in the Calico Mountains ..........200.002-.-----e-- eee 349 MSMEES DTC CCIANMMUCIMD OLY feezescc<: ccc creete cess bee5e 2205202 -ducesaecetteacse Jocecccecpcene bocce’ Spill omarbe py Mena C yas see ae coe 872i ets sek cece sat ey nccctesesee costa cadseesceecetebe tt eave 351 Structure of the Rosamond Series in the Calico Mountains -......... 352 The Rosamond Series in the Type Locality at Rosamond ................ 353 The Rosamond Series in Red Rock Cafion -......2.2...22.22002--1eeeeee eee 354 PAYS Om OMe te MROSAMONG SCTICS: soo tee ee ese fee ccc cea essed ecaceSsedeol settowglcesoue 357 Origin and Mode of Deposition of the Rosamond Series °..................... 357 334 Unversity of California Publications. [ GEOLOGY PAGE First Epoch of Deformation of the Rosamond Series .................---.--------- 360 The First Cyele of Post-Miocene Erosion ~.......2.22.2..202-22-2-::--:eeceeceeeeeeeeeeeos 361 Voleanic Activity near the End of the First Cycle of Post-Miocene XrOsion. 2 .2e.cSieee ik 366 Deformation following Epoch of Voleanie Activity and Beginning a New Cycle of Post-Miocene Erosion .........2..2..22.22.22-2:2::2seeceeeeeeeeeeoes 367 Fault Searps: ..i:.cc..acn ee nee 369 Rejuvenation: wa...4lea ie ee eee 369 Probable Antecedence of Black Cafion -.......2..2..222.220.22022.222122sc2eeeeeeeeeeee 370 Alluvial Slopes and) Playas (22822222 c:sse eres ee 371 Composition, Texture, and Structure -...........2..22..22..2-:--cce-eceeceeceeeeeeceeeee 371 Origin of Materials and Processes of Formation ~............-...2.2.222.-2------ 373 Dissection and Cafion-cutting in Alluvial Slopes —........2...0220.2022022.2-2-2--+ 37 Suggestions as to Correlation 2.22.22 378 Sim ary esos sf scceithe ic scs ede ieee a en 380 INTRODUCTION During the spring of 1911 the writer spent a period of two months in the western half of the Mohave Desert and adjoining areas for the purpose of collecting mammalian remains in the fossiliferous formations recently reported to oceur in that re- gion.t. In connection with this work it has been necessary to make a geologic reconnaissance of the formations concerned, and the following paper presents such results as it has been possible to obtain in the progress of the work. The field work was carried on in the interests of the department of palaeontology of the University of California. Mr. Wallace Gordon, of the University of California, assisted in the greater part of the field operations, and Mr. John R. Suman, of the same University, assisted in the examination of the Rosamond locality for the purpose of making a petrographic study of the rocks of that area. The author is also indebted to Mr. J. A. Sampson, Assist- ant in Petrography in the University of California, for prelim- inary determinations of rock specimens, and to Professor John C. Merriam for the opportunity of undertaking the work and for numerous suggestions during the progress of the field study and the preparation of the report. i Merriam, J. C., A collection of mammalian remains from Tertiary beds on the Mohave Desert. Univ. Calif. Publ., Bull. Dept. Geol., vol. 6, pp. 163-169, pl. 29, 1911. VO Un cml in34 r My, ii yy ui " ,, Ma y\ 7 %, fi a MH ul I, mG TS. \ Ss Z ZINN ae pe le Yt ous Cotton 20% $ ee ae yang RW) 4a =!) val LE LG Ol Rosamond ¥ J Oro Grant 2 Marble oi SCF airio 3 Granitic 4 Fost-/t, ----Foute of | Principat © We/l/ pus ny | } a | ‘ 3 v4 w JE\ A Ss Wg SAY BES NAR DITO c OSan| Bernaravno Givi. eorrio-» © 2. e rn ——S a =| offed/ands 139 "7° BULL. DEPT. GEOL. UNIV. CAL. VOL. 6, PL. 34 bBakerstyeld — aeeS — Fangs burg3 9 ~ Tonaqnesbury Nise "y x s keene is, 7 P (OTH Loop mie tey inte! titre eae e i 2 1C) ast /YTE LO} VALLE LEGEND. [1 fosamond Series I Oro Grande Series. 2 marble of San Bernar- > TURNER! je es PASS AN AWN. GELES Uiforvitt Es e A inna _—-« Flange > 3 Granitic Bedrock a & CQ <4 Post-/tiocene Lava. 3h > Ps) ~-—-Route of 19/1 Expedition. \ Principal roads an Co © well Qe iw a ® Spring aS ell | cal fi 17 Scale 750000 ce 6 iz é v3 ts 1911. 8° 10) PE, >! SAY seca M77. Pasadena hoe 1" 7) 3 8 SAN pEnngno! iad ° Perfor offed/ands “7 id AD on TAS nates ewpaiieonee dey Bye 2 } iM sti } f Fw AR HY : f ; aX aw ® - Bett S5 - iat ; { ae k Lee sid ‘ { t | ‘a i | a‘ : I 1 é 0 epee . Cy } t ; | | i ~ \ ; é ' cane am —_ a aeons ‘tors aay i H ‘ by ) ; } iH { “f ; i Sees rs) ; \ t J 5 i ; | H | ieee ee one et ever mer| get brn ten ea wate ane T Stee natn tases poe pacest ‘ i H i ; ee j a ss > 7h ey vinu JOG gO Jee ewer ae 7 “ Peres mau ah yb yan. cts, koe ran) is aces ‘ SANA WOKE cw revel £5 SONS N B GENE Seon e Py SAND! oni AO SON ae mst f Leyes Bunk! Veh Yo. vudk TOOK, Sa , ANOVEYES Vou.6] Baker: Cenozoic History of the Mohave Desert. O00 Although the expedition was made primarily for the purpose of collecting vertebrate fossils for a study of the extinet mam- malian fauna of this region, and the notes on the geology are consequently very fragmentary, it is hoped that the geological observations may be of some interest. The value of the results is very considerably lessened because of the lack of a suitable map, and therefore the locations and distribution given for the various rock members are only approximately correct. A de- tailed petrographic study of the rock specimens will probably be made at a later date. The route followed and the localities visited during the reconnaissance are shown on the accompanying sketch map® (pl. 34). LOCATION AND BOUNDARIES OF THE MOHAVE DESERT The Mohave Desert region comprises the extreme southwest- ern portion of the Great Basin. It les entirely within the State of California and includes within its limits portions of the four counties of San Bernardino, Inyo, Kern, and Los Angeles. Its boundaries on the northwest are the southern end of the Sierra Nevada Mountains and the Tehachapi Range; on the southwest are Sawmill Mountain, Liebre Mountain, the Sierra Pelon, with their southeastern continuation to the head of the Santa Clara River, and the San Gabriel Range; on the south are the San Bernardino Range and the Colorado Desert; on the southeast the natural boundary is the divide between the drain- age tributary to the Gulf of California and the interior drainage of the Great Basin. The eastern and northern boundaries are difficult to fix, for there the Mohave Desert merges into the Great Basin proper with no marked drainage divides or high bounding ranges. The northwestwardly directed Piute Range, just inside the California border, may perhaps best be chosen as the eastern boundary, north of the divide of the Colorado River drainage. The northern limits of the Mohave Desert will be given as an east-west line connecting Castle, High, and Clark’s 2 For a map giving approximate areal distribution of the rocks in a portion of the area herein discussed the reader is referred to Mr. O. H. Hershey’s ‘‘Geological Reconnaissance Sketch Map of Southern Cali- fornia,’’ Univ. Calif. Publ., Bull. Dept. Geol., vol. 8, pl. 1, 1902. 336 University of California Publications. | GEOLOGY peaks, near the Nevada line, and running through Leach’s Point and Burnt Rock Mountains to El Paso Peak, north of the mining eamps of Randsburg and Johannesburg. That the eastern and northern boundaries as thus outlined are given not without a measure of reason is shown by the fact that they define the limits between the northern Great Basin region of markedly parallel mountain ranges and the southern Mohave Desert region of lower ranges without notable parallel arrangement. METAMORPHIC, PLUTONIC, AND VOLCANIC ROCKS OLDER THAN THE UPPER MIOCENE The oldest rocks encountered in the region of the Mohave Desert were two series of metamorphosed sediments: the one exposed in the sharp hills east of Oro Grande station on the Atchison, Topeka, and Santa Fe Railway; the other outcrop- ping in the northern portion of the San Bernardino Range, in the northwest quadrant of the San Gorgonio Atlas Sheet of the United States Geological Survey. Plutonic rocks of a general eranitic composition intruded these two series of metamorphics and outcrop in many places in the Mohave Desert. The eroded surfaces of the plutonies are covered by lava flows in the vicinity of the town of Barstow. A much altered schist and gneiss, which has been referred to the Archean by Hershey,* outcrops just north of the Mohave River northwest of Barstow, flanking on the south a granitic range. THE ORO GRANDE SERIES A series of marbles, quartzites, and slates, which have already been described by Hershey,* is given this name because of the proximity of its outerop to Oro Grande station, which is situated less than a mile west of the western limit of the exposure. The quartzite is well cemented and exhibits planes of cleavage. Two varieties of marble were noted, one cream-colored with very coarse calcite crystals and the other with finer erystals and 3 Some crystalline rocks of southern California, Am. Geol., vol. 29, pp. 286-287, 1902. 4 Op. cit., pp. 287-289. Vou. 6] Baker: Cenozoic History of the Mohave Desert. Bon alternate white and gray bands. The slates are micaceous, prob- ably muscovitie, with very good cleavage into thin plates of large dimension, and probably form thin bands or lenses in the marble. The metamorphic series is tilted and faulted, and intruded by granitie rock with apophyses of orthoclase-muscovite pegmatite containing small dark-red garnets. Save the garnet, which was noted only in the pagmatite, no characteristic contact- metamorphic minerals were found. The series has been corre- lated by Hershey on purely lithologic grounds with the Lower Jambrian strata of Inyo County, California. . BASEMENT ROCKS OF THE SAN BERNARDINO RANGE A large body of altered limestone, in which characteristic contact-metamorphic minerals have been developed, has been intruded by granitic rock in Furnace Canon, in the northwest corner of the San Gorgonio Atlas Sheet. Two masses of the intrusive are connected by a dike varying from several hundred down to one hundred feet in width, which is more finely erystal- line at its borders than in the middle, and ean be easily traced across the slopes by its light. brown weathered outcrop. Masses of tremolite, with fibers varying in size from several inches in leneth down to minute needles, are extensively developed in the limestone hundreds of feet from the intrusive contact. This mineral is especially abundant in the vicinity of the Wild Rose mine, in Wild Rose Cafon, a tributary of Furnace Canon, where it makes up the greater part of the rock. The minerals ecyanite, epidote, chlorite, chaleopyrite, and specularite were noted close to the intrusive contact. Copper was found in very small lenses containing the original mineral chaleopyrite, in places second- arily enriched to chaleocite, with azurite and chrysocolla, min- erals of the zone of surface oxidation. Another body of contact- metamorphosed limestone was noted in Upper Holcomb Valley. Other metamorphie rocks of the San Bernardino Range com- prise argillaceous limestone with imperfect slaty cleavage, schists, and gneisses. The intrusive rocks found probably all belong to the family of granites, varying in texture from rather fine- erained dike rocks to very coarse-grained plutonies. A very coarse porphyry, with flesh-colored orthoclase phenocrysts as 338 Unwersity of California Publications. [GEOLOGY large as two inches in long diameter, outcrops on the north wall of the Santa Ana River Valley one mile north of The Pines, along the trail from Seven Oaks to Bear Valley, See. 5, Twp. 1 N, R. 1 E of the San Bernardino Base and Meridian lines. San Gorgonio Mountain, the summit of the San Bernardino Range, is composed of granitic rock and gneiss. GRANITIC BED-ROCK OF THE MOHAVE DESERT AND CONTIGUOUS RANGES The southern slopes of Granite Mountain, north of the wagon road from Victorville to Rabbit Springs, are composed of a granitic rock exhibiting the exfoliation characteristic of rocks of this general composition everywhere in the desert. Granitic rocks are also exposed in the vicinity of the town of Victorville, where the Mohave River has cut a narrows through them. They also outcrop in the ranges northeast, north, and northwest of Barstow, where at least a part of them are granodiorites, are crossed by the Southern Pacific Railroad between Rosamond and Mohave, are found in the Tehachapi Mountains west of Tehachapi Pass and at the pass, in the Sierra Nevada east of the pass, and east of Red Rock Cafon in the southerly spur of the El Paso Mountains which flank the Sierra Nevada on the south. These rocks vary considerably in color, composition, and texture and are cut rather commonly by pegmatite and aplite dikes. LAVAS PERHAPS EARLIER IN AGE THAN UPPER MIOCENE A lava flow of very basie andesite or of acid basalt overlies eranitic rock and underlies the basal beds of the Rosamond Series north of Barstow. Another lava, called by Gilbert® an ’ rests on a granitic ‘‘orange, massive, subspherulitie rhyolite,’ rock in Red Rock Cation, on the southern spur of the El Paso Range. Lindgren describes a rhyolite, upon which the Rosa- mond Series is deposited, in the Calico Mountains. These lavas may belong to the general period of the Rosamond Series, although their weathered and eroded surfaces indicate that they are very likely older. 5 Geogr. and Geol. expl. and Surv. west of 100th merid., vol. 3, pp. 142-148, 1875. Vou.6] Baker: Cenozoic History of the Mohave Desert. 339 THE ROSAMOND SERIES OF UPPER MIOCENE AGE DEFINITION AND DISTRIBUTION OF THE SERIES Hershey gave the name Rosamond Series in 1902° to a suc- cession of rocks which he characterized as being mainly rhyolitic in composition. The type loeality is north and northwest of Rosamond station on the Southern Pacific railway, near the north side of Antelope Valley, and mainly to the west of the railroad between Rosamond station and the town of Mohave. His type section, comprising 1650 feet of strata, is given as follows, beginning with the base: Type Section of the Rosamond Series wear Rosamond Station Thickness. Granite. 1. Coarse and fine white sandstone, composed of granite debris and rhyolitie tuff, thin-bedded, regularly stratified and dipping westerly at angles of Ji? to: 200 2... eee 500 ft. 2. Bright, light red, stratified sandstone containing granite debris, some cobbles and boulders (water worn) of granite and many angular and subangular fragments of white tuff... 50 3. Light yellow tuff mainly of rhyolite with an occasional pebble of granite; roughly stratified and dipping southerly —...........-...... 200 4. Massive dark red lava (apparently rhyolite) ; varies much in thick- MICSSyu QVCT ACID, Al OU see sececk <5. 28h e 2st se cesesavectatyeeue-sisrececenzece-- em 100 5. Light greenish and yellow rhyolite tuff, coarse in layers; contains abundant and large angular fragments of the underlying red lava and an occasional pebble and small boulder of granite; roughly stratified and dips southerly 10° to 380°... 400 6. White rhyolite, brecciated in layers ...........2.....2.22..---21ce-22eeeeeeeeeeeeeeeees 300 7. Light brown coarse sandstone; much granite debris and rhyolite; occurs in limited patches eapping knolls -........0..0...20.20..2.-22-22----- 100 Hershey finds the series in a low mountain four miles west and one mile north of Rosamond, and at Willow Springs Moun- tain, two miles farther northwest. The latter mountain he regards as the site of one of the rhyolite volcanoes. This voleanie belt seems to be represented in isolated patches along a line trending nearly due west along the northern border of Antelope Valley to its extreme western end. The purple and white lavas oeceur- ring in patches faulted down into the granite along the southern base of 6 Am. Geol., vol. 29, pp. 865-370, 1902. 340 University of California Publications. [ GEOLOGY the Tehachapi Range near Gorman’s station are on this line, are of similar composition and general appearance and doubtlessly belong to the same series. They go under the Upper Pliocene sandstone near Gorman’s station. The borax mines west of Fraser Mountain seem to be in con- nection with another patch of them. Probably many other isolated areas will be found in the southern Coast ranges (pp. 366-367). The Rosamond, according to Hershey, is found in the low mountain three miles south of Mohave, where the Exposed Treasure mine is located; in Soledad Peak, four miles south of Mohave; in many of the hills near the Santa Fe railway, five to seven miles southeast of Mohave; in Castle and Desert buttes, several miles north of Rogers dry lake; and in a narrow belt. rarely over several miles wide, trending eastwardly across Mohave Desert north of the line of the Santa Fe railway to beyond the town of Daggett. He suggests that the series also outcrops near Randsburg and for unknown distances east and south of Daggett. He includes within the series the sharp hills of lava outcropping in the Mohave River Valley in the vicinity of Barstow, and just northwest of Daggett he represents it as exhibiting the following phases: 1. Massive pink lava; appearance on casual survey much like ande- site, but on close inspection with a hand microscope it seems as acid as some rhyolites. 2. White and purplish rhyolite; slightly porphyritic, with flow struc- ture well developed so as to weather out with the appearance of a stratified formation, thin-bedded and highly tilted. 3. Breccia-conglomerate of lava and granite fragments. 4. Red sandstones and red shales. 5. Stratified fine and coarser tuffs of dark red color, tilted at a high angle. 6. Light red beds of coarse debris of pink granite, lava, ete. 7. A coarse, roughly stratified dark-red tuff containing fragments of black lava. The last bed is very thick. Its general appearance is like the red tuffs of the Escondido series. Indeed all the members from No. 3 to No. 7, inclusive, are strongly suggestive of the Escondido series. They dip away from, and seem to rest unconformably upon the massive rhyo- lites which are typically Rosamond. This only confirmed a suspicion which I had before that the Rosamond and the Escondido series are of about the same age, but that the former is slightly the older and fur- nished the material for the fine-textured, supposed rhyolite tuff stratum under the basic lava of Tick Cafion.* *Tiek Cafion is tributary to the Santa Clara River and this locality is about four miles north of Lang station on the Southern Pacific railroad. Vou.6] Baker: Cenozoic History of the Mohave Desert. 341 Remnants of a later series occur in Mohave River valley at several points, notably along the railroad about one and one-half miles east of Barstow. The following section, in descending order, of a bluff just north of the railroad, is typical of the series: Type-Section of Barstow Series near Barstow = . Stratified hard brown material due to arid conditions, but ceompo- sition not determined; persistent stratum over a considerable EELS eS NP eI roe 20 ft. Selly femol Uitkesate feaieiye sShnllts; ae eas ee 4 3. Stratified fine gravel and sand of dull red color and containing Te Coal cravat gto ev Our © Tit: S) pense seteeenebees mene eee venue cea UN ne aes 15 4. Structureless bed of white tuff with angular and subangular frag- ments of various other rock species embedded in it ............... 20 bo This formation is extensively developed on the low hills on the north side of the valley between Barstow and Daggett. It is thin, overlies unconformably the earlier series, and remains generally in a horizontal position, but has been extensively eroded. It is a valley formation made under arid conditions. In a small railway cutting near the bluff where the above was taken, this series is locally much broken up and overlaid uncon- formably by 20 feet of the nearly horizontal, roughly stratified, subang- ular gravel and clay which seem to form low Quaternary ridges on the south (pp. 368-370). The Rosamond Series was examined in five different localities during the recent reconnaissance. These localities comprise : (1) an area north of Barstow, in Township 11 N, Ranges 1, 2, and 3 W of the San Bernardino Base and Meridian lines; (2) a portion of the Calico Mountains north of the towns of Daggett and Otis, in Townships 10 and 11 N, Range 1 E; (3) Black Mountain, Townships 31 and 32 8, Ranges 44 and 45 E of the Mount Diablo Base and Meridian Line; (4) an area between Rosamond and Mohave in Townships 9 and 10 N, Ranges 12 and 13 W, and Township 11 N, Range 12 W of the San Bernardino Base and Meridian lines; and (5) in the region centering about Ricardo postoffice, in Red Rock Canon, on the southern spur of the El Paso Mountains, in Townships 29 and 30 S, Ranges 36 and 37 E. In all these localities the series has a general east- west strike. In the above localities the Rosamond is mainly a sedimentary series, with only a subordinate amount of both acidie and basic lava flows. The sediments are mainly breccias, with fragments 342 Unwersity of Califorma Publications. [GEOLOGY of granitic materials and lavas and matrices of finer arkoses, voleanie ash, and chemical precipitates. Tuff-breccias, finer tuffs, and shales and mudstones with interbedded layers of gypsum, ealeium carbonate, and borax minerals occur in subordinate amounts. Conglomerates of water-worn boulders are of rather rare occurrence. ROSAMOND EXPOSURE NORTH OF BARSTOW The Rosamond here attains its maximum known development both in thickness and diversity. The approximate thickness of the series cannot be much less than a mile, although faulting has rendered difficult the determination of the exact thickness. In this exposure there are at least five mapable units, but not all of the five have yet been found in any other single locality. Basal Breccia Member.—The base of the Rosamond is every- where marked by an erosion unconformity with a basal breccia resting on weathered surfaces of granitic rocks and lavas (pl. 354). At the base of the south limb of the Barstow syncline a distinct basal breccia of mapable thickness occurs, resting on the eroded surfaces of both granodiorite and a basic andesite or acid basalt, and containing fragments of both of these rocks. The member is mainly dark brick-red in color and at least sev- eral hundred feet thick, although the displacements caused by two strike faults makes its exact thickness uncertain. The frag- ments are mostly angular or subangular, but some rounded pebbles and boulders which probably owe their form to exfolli- ation, as indicated by their rough surfaces, are found. The fragments are rather small, ranging up to six inches in diameter. The matrix is mainly arkosic, being largely disaggregated frag- ments of quartz and feldspar derived from the granodiorite. A basal breccia of this same type was found resting on granitic rock at the base of the north limb of the syncline, at the north- west end of the exposure, but farther east the basal beds contain such a large proportion of voleanic ash that they may more appropriately be included in the next member. Tuff-breccia Member.— (PI. 358.) This differs from the basal breecia member in being mainly composed of finer fragments, in generally containing less granitic material, and in having in BULL. DEPT, GEOL. UNIV. CAL. WA@IE Mey tir sis’ A. Contact of basal breccia member of Rosamond Series with basic andesite or acid basalt, north limb of Barstow syneline. The lighter portion of the lava next the con- tact is more weathered than the darker portion to the right. B. Tuff breecia member of Rosamond Series resting on granitic voek with erosion unconformity at base of north limb of Barstow syneline. The graded profile of the granitic rock surface at the left and the strike valley in the center should be noted, Vou.6] Baker: Cenozoic History of the Mohave Desert. 343 general a much larger proportion of voleanic ash in its matrix. It does not weather into badland forms, but produces rounded hills or cliffs of rather bold, shagey outline. It is considerably over a thousand feet in thickness in the north limb of the Bars- tow syneline, with its upper hmit defined by an unconformity eof unknown extent. The member is made up of highly varie- gated thick bands of whitish, cream-colored, pink, red, lavender, purple, brown, and green tuff-breecia. The colors are very bright and their frequent alternations present some striking contrasts. The breccia fragments are of white and variously colored tuffs and lava with colors ranging in almost all gradations from white to black. The lava fragments exhibit various degrees of alter- ation and in some fragments flow structure was noted. Locally fragments of granitic rock occur and the base of the member rests upon granitic rock. Fine Ashy and Shaly Tuff Member.—(P1. 36a.) This mem- ber outcrops in the south limb of the Barstow syncline where its southern limit is defined by a strike-fault of unknown dis- placement which separates it from the basal breccia member. The lower beds are mainly composed of a greenish-gray rather fine unconsolidated ash, with thin, more resistant layers. .co Verse: Paes ee a ee SEN 12. New Ichthyosauria from the Upper Triassic of California, by John C. Merriam... : 13. Spodumene from San Diego County, California, by Waldemar T. Schaller................ a 14. The Pliocene and Quaternary Canidae of the Great Valley of California, by John C. Merriam ......... deca Lacocsatenocnc ict cenaet Me een ot Sires Let ona aCMenet gates Ne See 15. The Geomorphogeny of the Upper Kern Basin, by Andrew C. Lawson.................... 16. A Note on the Fauna of the Lower Miocene in California, by John C. Merriam... 17. The Orbieular Gabbro at Dehesa, San Diego County, California, by Andrew C. ~ Lawson ASS : : 18. A New Cestraciont Spine from the Lower Triassie of Idaho, by Herbert M, Ev 19. A Fossil Egg from Arizona, by Wm. Conger Morgan and Marion Clover Tallm 20, Euceratherium, a New Ungulate from the Quaternary Caves of California, b; William J. Sinclair and H. L. Furlong .......-----.-n--2:--eeces-eseen-o== Pret tty eases 21. A New Marine Reptile from the Triassic of California, by John C. Merriam 92. The River Terraces of the Orleans Basin, California, by Oscar H. Hershey.. ore BSS wo oH UNIVERSITY OF CALIFORNIA PUBLICATIONS BULLETIN OF THE DEPARTMENT OF GEOLOGY Vol. 6, No. 18, pp. 403-412 Issued November 1, 1911 NOTES ON THE GENUS DESMOSTYLUS OF MARSH BY JOHN C. MERRIAM CONTENTS Introduction Occurrence 1D XSpaT RL CAC rot Sevens ek eee ee RRR 5 ae er AA eR OY Ae INTRODUCTION The peculiar mammalian genus Desmostylus described by Marsh’ as a sirenian is of considerable interest to palaeontolo- gists, as it represents a pecular combination of proboscidean and sirenian characters. It is, however, one of the most imper- feetly known of the Pacifie Coast vertebrate forms, the total amount of American material available for study ineluding only a few teeth and some scattered fragments of skeletal elements. Recent discoveries seem to show that Desmostylus may be a valu- able horizon determiner in geologic work in California, and may also have some importance in geological correlation between America and Asia. It has, therefore, seemed desirable to bring together all of the information available concerning this form, in the hope that such a statement may assist in the accumulation of further data relating to its structure and range. 1 Marsh, O. C., Am. Jour. Se., vol. 35, pp. 94 to 96, 1888. 404 University of California Publications. [| GEOLOGY OCCURRENCE Particular attention has already been called? to the fact that all Desmostylus material of which definite information could be obtained has been found in marine beds. This statement. is, however, not in accord with that of Marsh, according to whom the type material was found in association with remains of mastodon, camel, a large edentate, and one or more species of horse. Since the publication of his note on this subject it has been the writer’s privilege to examine Marsh’s type of Desmostylus, through the courtesy of Professor Richard 8S. Lull, of Yale University. Contrary to the statement in Marsh’s description, it was found that the original label describes the tvpe of Desmostylus as coming from Contra Costa County, Cali- fornia, where it apparently occurred in association with marine Miocene invertebrates. One of the specimens is embedded in rock similar to that of one phase of the marine Miocene of middle California. The only objection to considering Desmostylus as a marine form has, therefore, disappeared. It is to be presumed that the animal may have occupied the mouths of rivers and could, therefore, be found in estuary or even in river deposits. Within the last few years a number of occurrences have come to heht which indicate collectively that Desmostylus is limited to a comparatively narrow geologic zone of the Tertiary, and is presumably of value as a means of correlating widely separated deposits. Numerous fragments of Desmostylus teeth have been found by Mr. F. M. Anderson to the north of Coalinga, in the western part of the San Joaquin Valley, in beds designated by him as the Temblor formation. As nearly as can be determined, Des- mostylus does not oceur either above or below this zone in this region. ycon'oo * the Palaeontology of the Martinez Group, by Charles E. om ce Tmpe.d cithy Known Rodents and Ungulates from the John Day Sei A SRRME: SYS SMES BMRB 012 aS RP es Ss Oo or et aR ee CREE ae te ieee ae hew Mawme from thé Quaternary Caves of California, by William J. ¢ . Preptoceras, 1 Mew Ungulate from the Samwel Cave, California, by. Eusi.: Peajongy whe. RE ete EEE SoRCE EES acorn swe cuy 0- oun hy Sent au Sean 5 ee Ie eB a gue Oioxe Ripre-toc (trom) California, by John’ C: Merriam \...23..2..28.6..07-0-, Leo Struc bare aid Genesis of the Comstock Lode, by John A, Reid................ . ‘he Differential Thermal Conducetivities of Certain Schists, by Paul Thelen it Sketch. of the L'e.logy of Mineral King, California, by A. Knopf and P. The. iS. Cold Water “-° Along the West Coast of the United States, by Ruliff S. B 34; 3 ae upper ) sits of the Robinson Mining District, Nevada, by Andr a, Teen ty oe viion $o the Classification of the Amphiboles. pe we Bs Hate Gle reophane Schists, Syenites, ete., by G. Murgoei....-...2.0.2...... G6. The “aevsrphie Beatures of the Middle Kern, os Andrew C. Lawson........... 7 Notes or the J .'thill Copper Belt of the Sierra Nevada, by A. Knopf. . Sn Afverntian of Coast Range Serpentine, by A. Knopf. I OSE CAN Galess MONG CGO ED cantawae cme at A Sreatt nc uence SNe et . The Peamorphog: ny of the Tehachapi Valley System, &;: Andrew C. Lawson... VOLUME 5. . “sostvota frou. he Tertiary Formations of the John Day Region, by Jol Merriam SR 8 NS ote SaaS ae. Bh Ete ean esp oe, AMER ee SE GR a RR aera BCE . Some dentate! ce Remains from the Maseall Beds of Oregon, by Willia MNCL, Voss Mothusee om the John Day and Mascall Beds of Oregon, by Robert PLGATAS Nos. 20a PRION COV OMe. escree. se erat Nine cates abet CePA eee Oe Net cas waeaoeat ne ‘eeth from the West American Triassic, by Edna M. Wempl) y “o on a New Marine Reptile from the Middle Triassic of Ne Bhtce co Tawar .je, Columbite, Beryl, Barite, and Calcite, by Arthur S. Eakl) tis Bossi! J is) of California, with Supplementary Notes on Other Speci att eviunely Wiske-, xDawmidestarr, denmann 27 220 ee % “ie, Retulay © » 1 the Marine Lower Triassic of Aspen Ridge, Idaho, by Ma’: Foddare 2a... eee Aa hm ate St tee BN ge Sees ReaD No ok Sa ant oastccanseescaees 2 eutteites. aN California Gem Mineral, by George Davis Louderback, Chermic¢a) ‘Ane |» sib walter: Crablasd alec Se. Te ae aac onrel 195 Neles on (mate... ry Belidae from California, by John F. Bovard.............-2..4| Ti ferviary Bouun: £ the John Day Region, by John C. lekiedoa and Willia ARC) Bab MO SN PR PRGA BS 2 on ae a Se 12, (punt “pods and Insects of California, by Fordyce Grinnell, Jr........ 13, 42 f ology of the Thalattosaurian Genus Neéctosaurus, by John 28. Netes on S: ‘\lifornia Minerals, by Arthur S. Halle... tees 15. Woies on “on of Fossil Mammals from Virgin Valley, Nevada, by J WY ilian 6 |. ies wneeSebeagidns «eee ness one pao ig eS “ ms Se ; . a ’ ¥ : é : VOLUME 5—(Continued). La Brea, by Lcye Holmes Miller eee eee ean n een anne ewan en ne saan se eenaneee) siceeneaeee John C. Merriam Nevada; by. John: C.. Merriam scp e..-..../..-s-10 ee with chemical analyses by Walter C. Blasdale..... 00... by. adie ©. Merriam... 2. ocasictaee eens ce, oe ee oe eee An Aplodont Rodent from the Tertiary of Nevada, by Eustac3 1 AOAC US AG UD CFG is secce- sit --neb oe cadee noe. hese eee PEDO MA ACW OP oes sea eacaact specter Sane na cekendivassaacee cet cre pe saee ane Nevada, by Louise Kellogg cc. 2... Secs eee ee iain Miler 1:05 2.0... ee ea, . VOLUME 6-— w— ada, by John C. Merriam. Part I—Geologic History... duorye, Etolmes Mien 2c. 0h. ogo sordet--t tence tnae coon Soe ten oe The Geomorphogeny of the Sierra Nevada Northeast of Lake Tahoo, by Merriam. by John C. Merriam. INOS; Geand 7 In, ONE “COVET .. 22, tac ons.ncacateaseel cose asinagoea optus re The Stratigraphic and Faunal Relations of the Martinez Toes and Tejon North of Mount Diablo, by Roy HE. Dickerson 2222 County, California, by Arthur S. Wakle 7 coltrane Nevada, by John C. Merriam. Part I1.—Vertebrate Faunas ........ IMI er ook Salts case on cece cdanseennetonadncceupocch seks dsticeactscndsiva atseee ae er rr of Spitzbergen by Wiman, by John C. Merriam. Nos, 13 and 14 in: one covers../..23 ee California, by Charles Laurence Baker ..2...22c--2csei 2st cceccesenccennaeceensenteeee if 1 Li ; Meu GG een nla nh! Peg Ai wal i Rae) y ; d ae rte rea ‘ i Nah , rey Ane nh eV one ae a KURO Ley Ryn via Tatok (ie ty Nin, yee Ht Dine Y i ens as aes if fh THO) LA iy 4 on Ne Nahe Bt ath § val th ee MMT) Aya) Ni } ‘ i Ani pi Ui Tey Wanye! (hu, Na ADs i eae Piha Ae A am ‘alee be ay ne WEN Oot Hoh on Hy ty ‘ cE eh Bsa utens hig j abn ti f al ES i. ef CBr ee, | | i My rer apr ag te Aas ya AA, patna tn 4q-. aaa\) a | Mepinny, pr ar VEAL aL PH Ae } i < ogy Oe Na pearere’ (8gaa eA RRA can, , aaa } p me VA Wea}, *osca,yaatnana © oo papbar seine’ & parte eae Ana revit. Mosaqyytthomenr : hy me ‘ : SEGRELEE anes? f EY Lae @ 1 “Hag Aaa SAN AAAaag) sMinapeeeennRRGtelinat AGtia.! wali a! & Aaa aAKa aah ane... 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