Here's a popular Dr. Seuss story! Poor Horton gets duped into watching an egg while it's mother goes on vacation. What a bad parent.
Another Dr. Seuss story, The Grinch That Stole Christmas, was translated to film by the Warner Bros cartoon director Chuck Jones. That's a classic Christmas TV special.
But did you know, before The Grinch, Horton the elephant was animated in a Looney Tunes short! Back in 1942, Bob Clampett, the zaniest Warner Bros cartoon director, took Seuss' story and made a special 91/2 minute short out of it.
A couple of interesting gags appeared in the cartoon that were not in the original. A fish caricature of Peter Lorre says, upon seeing Horton pass by in a ship, "Now I've seen everything" and promptly shoots himself in the head (a grisly staple of the "Termite Terrace" gag writers). Mayzie also does a breathy Katharine Hepburn ("raaaaaaaa-hlly I do") at several points. The cheerful elephant (along with his son, at the end) sing a popular nonsense tune of that era, "The Hut-Sut Song".