PAPILIONIDiE. 
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head, have a convex breast and a hump on the thorax. Many of 
them are green in color. 
Colias pliilodice. Male. 
Our best known species of this genus is Colias pliilodice , an 
insect which ranges over the whole of our country east of the Rocky 
Mountains. It is common in summer in almost every field, and 
may be seen by dozens quietly resting with wings erect, sucking 
Colias pliilodice. Female. 
the moisture from the muddy pools in the roads. A good many 
varieties occur, and one may find many albinos and also dark rich 
specimens if the trouble be taken to search for them. The caterpillar 
feeds on the clover. It is grass green and striped with light green. 
