Droopy

The character first appeared, nameless, in Avery's 1943 cartoon Dumb-hounded. Though he would not be called "Droopy" onscreen until his fifth cartoon, Señor Droopy (1949), the character was officially first labeled Happy Hound, a name used in the character's appearances in Our Gang Comics. After the demise of the Droopy series in 1958, the character has been revived several times for new productions, often television shows also featuring MGM's other famous cartoon stars, Tom and Jerry.
Droopy is an animated cartoon character, an anthropomorphic dog (supposedly a basset hound) with a droopy face, hence the name Droopy. He was created by Tex Avery, for theatrical cartoon shorts produced by the Metro-Goldwyn-Mayer cartoon studio, in 1943. Essentially the polar opposite of Avery's other famous MGM character, the loud and wacky Screwy Squirrel, Droopy moved slowly and lethargically, spoke in a jowly monotone, and, though he didn't look like much, was shrewd enough to outwit his enemies and when angered was capable of brutally beating adversaries twice his size.
from wikipedia