Term: Des Plaines River, Racine Co.
From Increase Lapham's 1844 Geographical and Topographical Description of Wisconsin:
"The DES PLAINES, is another branch of the Illinois river, that rises in Racine county. It is usually called the O'Plaine. Its name is derived from a species of maple called plaine, by the French. Its aboriginal name was She-shik-ma-o."
[Source: as above]