Today in history: 27 July 1940

A Wild Hare (re-released as The Wild Hare) is a 1940 Warner Bros. Merrie Melodies animated short film. It was produced by Leon Schlesinger Productions, directed by Tex Avery, and written by Rich Hogan. It was originally released on this date. A Wild Hare is considered by many film historians to be the first "official" Bugs Bunny cartoon.
Bugs is unnamed in this film, but would be named for the first time in his next short, Elmer's Pet Rabbit, directed by Chuck Jones. The opening lines of both characters—"Be vewy, vewy quiet, I'm hunting wabbits" for Elmer, and "Eh, what's up Doc?" for the rabbit—would become catchphrases throughout their subsequent films.
In the original version, when Bugs plays "Guess Who" with Elmer, Elmer's second answer was Carole Lombard. In the reissue prints released following Lombard's death in a plane crash, "Carole Lombard" was redubbed with "Barbara Stanwyck."
If you can you look close enough, you can see that before it says MCMXL (1940), it says MCMXLIV (The Blue Ribbon reissue was made in 1944). It quickly changes to MCMXL with a big black outline (So that MCMXLIV cannot be seen).

[ame="http://www.youtube.com/watch?v=qGqN_nXDaQc"]Bugs Bunny- A Wild Hare - YouTube[/ame]