ILLINOIS BIOLOGICAL MONOGRAPHS 



[510 



PLATE XXIII 



Explanation of Plate 



Figure 470. Showing the range of variation in the group of races included 

 under C. scuiellaris Say. General plan as in figure 469, plate XXI. Here the 

 individuals are arranged into classes which are strictly geographic ; beginning in 

 Massachusetts at the extreme left, they are arranged as encountered as one passes 

 southward along the Atlantic coast and westward through the Gulf States. From 

 Dallas, Texas, classes are arranged in order as one passes northward through 

 western Oklahoma, Kansas, Nebraska, and South Dakota and tlien eastward 

 through the Great Lakes. The classes on the extreme right (s and are from 

 Aweme, Manitoba. 



