232 



THE CHICAGO ACADEMY OF SCIENCES 



GEOLOGICAL RANGE (Figure 20) : Pleistocene. The geological 

 range of caperata is not as extensive, judged by the records, as is its 

 recent range. The records are sufficiently numerous, however, to indi- 

 cate a wide extension in the Upper Mississippiari and Canadian regions. 

 None of the records are preglacial. It is a characteristic Loess fossil 

 owing to its peculiar habitat. Further Loess researches will doubtless 

 largely extend the range herein indicated. 



Geological 



Distribution 



CAPERATA 



FIG. 20. 



LOESS. 



IOWA : Fremont and Mills Counties, Iowa, in bluffs bordering the Missouri 

 River (Call) ; Loess of Iowa (Keyes; Shimek) ; Lcess of Iowa City, Johnson Co. 

 (McGee, smaller than living form; Shimek); Bluff above Hershey Avenue, 

 Muscatine, Muscatine Co. ; Division ; St. Davenport, Scott Co., near base of 

 Lcess (Leverett; Shimek; Udden) ; 2^2 miles north-east of Minden, Pottawat- 

 tamie Co. ; Nebraska City, Fremont Co., and Sioux City, Woodbury Co. ; Scott 

 and Johnson Counties (Shimek). 



INDIANA: New Harmony, Posey Co. (Daniels; Weller.) 



NEBRASKA: Lancaster Co. (Shimek). 



SAND AND GRAVEL DEPOSITS. 



ILLINOIS : Sand banks along Lake Michigan shore, north of Graceland 

 Avenue, Chicago (Jensen). 



CANADA: Sand and gravel pits near Niagara Falls (Bell; Can. Geol. 

 Surv.). 



