Groucho Marx called her "practically the fifth Marx Brother".
Biography in: "Who's Who in Comedy" by Ronald L. Smith. Pg. 143-144. New York: Facts on File, 1992. ISBN 0816023387
Her screen persona was that of a stolid, wealthy society matron, which is exactly what she was: her husband, John Moller, was a millionaire industrialist, and she often commuted to filming locations from her mansions in Palm Springs, California, and Paris, France.
Last appearance of any kind was on the TV show "The Hollywood Palace" (1964) in 1965, reprising her role as Groucho Marx's straight woman. She died just days later.
Offstage, she usually called Groucho Marx "Julie", which is short for Julius, Groucho's given name.
Profiled in book "Funny Ladies" by Stephen Silverman. 
She was bald and wore wigs for several years on and off camera.
She was the god-daughter of author Joel Chandler Harris.
Some have argued that her image of the refined lady who did not understand The Marx Brothers' humor was an artificial one, since she had a long career being a comedic foil in comedy stage productions years before her more famous work. However, Groucho Marx himself has said on numerous occasions that she really didn't understand most of the Marx Brothers' humor.
Started on stage in 1907