Jack L. Warner found he could save a little money by reissuing old Warner Brothers cartoons with less footage. He cut out the original title sequences and replaced them with two cards: one that identified the name of the series and one the name of the film. The series card always said "Merrie Melodies" even if the films were originally Looney Tunes. The title card eliminated the credits and sometimes even got the title wrong. Thus
A Wild Hare (1940) became The Wild Hare.
These are the Blue Ribbon reissue prints. The restorers did their best to find the original title sequences, but did not succeed with every film. If you see "Blue Ribbon" on a Warner Brothers cartoon, you know you're not getting the original title sequence.
Source: this film. Also see Merrie Melodies on Wikipedia.