Fleas in the dictionary

The discussion on the Discovery News Podcast about dictionaries got me thinking as to if this would answer the question of when the term "flea circus" was first used.

We know that back in Bertolotto's time the performances were not described as a circus but as an exhibit. We also know that Egon Erwin Kisch who was a fan of Charles Dicken's "Sketches by Boz" used the term "Flea Theatre" in his 1920s book "Die Abenteuer in Prag". In approximately 1901 strong man William Heckler took over an Orlando, Florida "Flea Theater" and John C. Ruhl also ran a "Flea Theater" at Hubert's. By 1925, the Heckler's had taken over with their "Trained Fleas", according to a show flier they were using the term "Trained Flea Circus" for their show in Time Square by 1934.

My initial searches brought up nothing, flea circus is not in the dictionary. I'm guessing that this is because it's a "phrase" not a "word". It's also not in the official list of scrabble words.

However a trip to Westminster reference library in my lunch break found the phrase in the 2007 6th Edition Oxford English Dictionary, the 2nd Edition Oxford English Dictionary and Chambers 11th Editionary Dictionary. The OED also suggested that the phrase was from US origins. Although the librarian did offer to search online for me, I did not have time on this visit. The librarian was also skeptical that the early editions of the dictionary would contain the phrase.