The Rabbit Hood is a fairy-sized version of the Bunny Hood worn by Ravio.
In the cartoon the Sheriff of Nottingham catches Bugs eating the King's carrots and is about to arrest him, when Little John shows up and tells them that Robin Hood is on his way. The cartoon ends with the appearance of "the real" Robin Hood in the form of a clip from the classic 1939 movie (The Adventures of Robin Hood), which starred Errol Flynn (he received a personal copy of this film in exchange for the right to use his earlier image).
This cartoon is the origin of the infamous "knighting" exchange, where Bugs Bunny is dressed up like a king, and proceeds to pound the skull of the Sheriff with his sceptre while dispensing an oddball title with each strike: