FAQ

Merrie Melodies.

Various sources have stated that the character Casper Caveman in this cartoon is a caricature of Jack Benny. Well, yes and no. The vocal performance (by Jack Lescoulie) expertly copies Benny's distinctive delivery and some of his catchphrases ('Good night, folks.'), and [Chuck Jones]'s animation even duplicates a few of Benny's gestures. However, the character as drawn simply doesn't look like Benny, neither facially nor physically. I wonder if this was an attempt to avoid a lawsuit. Or perhaps it was [due] to the fact that Jack Benny (who had already made some film appearances dating back to the late 1920s) was at this point best known as a radio star, so movie audiences might not be sure of what he looked like.

An advertisement for 'Duckies' in this toon is a parody of a contemporary real-world ad for 'Luckies', i.e., Lucky Strike Cigarettes, which were the long-term sponsor of Jack Benny's radio show. (He had better luck with his next sponsor, Jell-O.)From: F. Gwynplaine MacIntyre's IMDb user comment

See also: Wikipedia's page for Jack Benny

Some prints cut out the fade-out/fade-in that occurs between two scenes near the end. This was probably done just to shorten the cartoon, rather than censor anything objectionable.