Janet Blair, 85, the vivacious actress who appeared in several 1940s musicals and comedies, then turned to television and stars such as Sid Caesar and Henry Fonda, died Feb. 19 at Saint John's Health Center in Santa Monica, Calif. She had pneumonia.

Ms. Blair was singing with Hal Kemp's band at the Cocoanut Grove in Los Angeles in 1941 when she was spotted by a talent scout from Columbia Pictures shortly before Kemp was killed in a traffic accident. She had landed an audition with the bandleader at age 18 through a family friend.

When the musicians decided to disband after Kemp's death, Ms. Blair signed a contract with Columbia for $100 a week and changed careers.

She would languish in B pictures until Rosalind Russell recommended her for the title role in the comedy "My Sister Eileen" (1942). She won praise from critics for her performance as Russell's beautiful but trouble-prone sister.

She appeared opposite George Raft in the gangster movie "Broadway" and co-starred with Cary Grant and a dancing caterpillar in the 1944 comedy-fantasy "Once Upon a Time." She was the love interest in "The Fabulous Dorseys" (1947), starring bandleaders Jimmy and Tommy Dorsey, and appeared opposite Red Skelton in "The Fuller Brush Man" (1948).

After the 1948 swashbuckler "The Black Arrow," Columbia dropped her and she moved on to theater and television.

"I gave up Hollywood and I gave up pictures because I was always getting parts where I'd be the girl who says, 'Oh, Red!' in a Skelton movie," she said. "All I got were princess parts. A girl gets tired of being a princess all of the time."

Instead, she took on the Mary Martin role in the touring version of "South Pacific," clocking more than 1,200 performances in three years.

She appeared on television shows such as "Ford Theatre," "Philco Television Playhouse," "Lux Video Theatre" and "U.S. Steel Hour."

She joined television's "Caesar's Hour" in 1956 when Sid Caesar was seeking a replacement for co-star Nanette Fabray. She left after just one season, complaining she was "not given the opportunity I had been led to believe I'd get."

She returned to movies in 1957, starring opposite Skelton again, in "Public Pigeon No. 1."

Born Martha Janet Lafferty in 1921 in Altoona, Pa., Ms. Blair attended public schools and sang in the church choir. She would later take the name of a Pennsylvania county in christening herself Janet Blair.