HOW TO KNOW THE BUTTERFLIES 



and the outer margin is more or less dusky; the hind wings 

 are without spots. 



In the female the bar at the outer end of cell R + M and 

 the submarginal spots are present and are more conspicuous 

 than in the male. There is in addition to these, on the upper 

 surface, a row of triangular spots on the outer margin of both 

 fore and hind wings, and a submarginal zigzag bar on the 

 hind wings. On the lower surface, the veins, especially of 

 the hind wings, are more or less tinged with greenish yellow, 

 and flecked with gray. 



Expanse of wings one and six-tenths inches to two and one- 

 fourth inches. 



(2) The Spring Form, Pontia protodice vernalis. — This 

 form of the species is much smaller than the typical one ; it 

 appears in early spring, and in much smaller numbers than 

 the later broods, which are of the typical form. On the lower 

 surface the greenish-gray banding of the veins of the hind 

 wings is much broader, so that the white is reduced to narrow, 

 wedge-shaped spots. 



Caterpillar. — Length about an inch. The body is 

 cylindrical and downy. It is striped lengthwise with yellow 

 and greenish purple dotted finely with black. It has a small 

 head. 



Food-plants . — Cabbage and other Cruciferae 



The females of this species are the ones that are 

 attired in checkered raiment, the males being 

 dotted rather than checkered, which, by the way 

 is not a very good term for the beautiful diamond 

 design on the wings of the female. The cater- 



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