I stumbled across this image the other day and got curious. I could only find a few facts: this troupe of little people was managed by German born Oscar Klinkhart (ca.1897-1975). They were with with the Al G. Barnes show between 1926 and 1931. According to some sources, they were later with Hagenbeck-Wallace Circus and got stranded near Riverside, California ca. 1936, where they founded one of the many legendary “Midgetville” communities. Later Klinkhart retired to Logsden, Orgeon.
For more on show biz history, consult No Applause, Just Throw Money: The Book That Made Vaudeville Famous, available at Amazon, Barnes and Noble, and wherever nutty books are sold.