For the scene where Dan Quigley hauls Myra Gale across the apartment floor by her hair, and throws her out the door, James Cagney taught his co-star Mae Clarke an old stage trick. When Cagney grabbed hold of Clarke's hair (holding her by the top of her head), Clarke reached up and grabbed Cagney's wrist with both hands. This put her weight on Cagney's wrist, instead of on her hair. Clarke then held on to Cagney's wrist, screaming as he dragged her across the room.
When Myra (Mae Clarke) is reading from the California travel brochure, she gets a worried look on her face when she reads "Grapefruit." This is a reference to The Public Enemy (1931) (which also stars James Cagney and Clarke) where Cagney's character pushes a grapefruit into the face of hers.
After James Cagney, dressed as a native American, dismounts a mechanical horse, he finds it painful to sit down in Lois' dressing room. When she enters and asks him what he's made up for, Cagney, who was fluent in Yiddish, responds "Big Chief Es Tut Mir Veh im Tuchas," which delicately translated means "Big Chief It Hurts My Rear End."
Dan Quigley's fan mail scam actually had a real-life precedent: Ivan Lebedeff was cast in several prominent roles by RKO before they realized that a majority of fan mail for him they had received had actually been written by Lebedeff himself.
Included among the American Film Institute's 2000 list of the 500 movies nominated for the Top 100 Funniest American Movies.