Jones joined Leon Schlesinger Productions, the independent studio that produced Looney Tunes and Merrie Melodies for Warner Bros., in 1933 as an assistant animator. In 1935, he was promoted to animator and assigned to work with a new Schlesinger director, Tex Avery. There was no room for the new Avery unit in Schlesinger's small studio, so Avery, Jones, and fellow animators Bob Clampett, Virgil Ross, and Sid Sutherland were moved into a small adjacent building they dubbed "Termite Terrace". When Clampett was promoted to director in 1937, Jones was assigned to his unit; the Clampett unit was briefly assigned to work with Jones' old employer, Ub Iwerks when Iwerks subcontracted four cartoons to Schlesinger in 1937. Jones became a director (or "supervisor", the original title for an animation director in the studio) himself in 1938 when Frank Tashlin left the studio. The following year Jones created his first major character, Sniffles, a cute Disney-style mouse, who went on to star in twelve Warner Bros. cartoons.