As I have pointed out before, Harpo was posthumously baptized as a Mormon. Still, you wouldn't expect the Utah State Historical Society to be a rich source of Marx Brothers history. You'd be wrong, because the USHS has produced a very interesting page related to the premiere of the stage version of "A Night at the Opera" in 1935. MGM producer Irving Thalberg arranged for the brothers to road test the show in Salt Lake City, Seattle, Portland, and San Francisco before filming began. Audience reaction was carefully observed in order to fine tune the script and timing of "Opera." I'll leave it to the interested reader to click over to the USHS site for details.
I'd also like to point out a link provided by USHS. It is a page of material deleted from the original script. Some of the stuff is pretty good, IMHO. For example:
Driftwood (to the cab driver when he learns that he has arrived at the opera house before the opera is over): On account of you, I nearly heard the opera! Next time I go to the opera, I'll take a turtle. At least with a turtle you've got something. When you get tired of it, you can make turtle soup. Of course, you can get turtle soup in cans. But you can't go to the opera in a can. On the other hand, you can't go to the can in an opera.To read more, click on this link.