A prolific radio and TV actress, Ms. Mitchell was a regular on such classic radio series as "Fibber McGee and Molly" and "The Great Gildersleeve," and on television, "Pete & Gladys" (Janet Colton), "Please Don't Eat the Daisies" (Marge Thornton), and "Bachelor Father" (Kitty Deveraux). She also made frequent appearances on other TV shows, including "The Dick Van Dyke Show" and "Perry Mason." Ms. Mitchell's feature film credits include "Desk Set," "Big Business," and "The War of the Roses." Best Known for playing Lucy Ricardo's girlfriend, Marion Strong on I Love Lucy, in "Lucy and Ethel Buy the Same Dress" (Episode #69). She made two more appearances as Marion, on "Lucy's Club Dance", and on "Lucy Tells the Truth". She was the wife of composer Jay Livingston (1915-2001).