THE PIERIDS 



The Orange Sulphur 



Eurymus eurytheme (Eu'ry-mus eu-ryth'e-me) 



Plate XVII, Fi<;. 4 



This species closely resembles philodice in size, shape, and 

 markings. The typical form differs from philodice in being 

 of an orange color instead of yellow above ; the costal margin 

 of both wings and the inner margin of the hind wings are, 

 however, yellow. Except in this difference in the ground 

 color of the wings, the description of the clouded sulphur 

 given above will apply quite closely to the more common form 

 of this species. 



This is one of the most polymorphic of all butterflies, and 

 the forms differ so much that they have been described 

 several times as distinct species. The typical form described 

 above is the only one occurring in the East. 



Caterpillar. — Length nearly one and one-fourth inches. 

 Color grass-green, with an indistinct line down the back. 

 Along each side of the back is a white stripe on which are 

 irregular patches of vermillion or orange yellow ; at the 

 center of each segment below the stripe are darker markings. 



Food-plants. — Clover, buffalo-clover in the West, milk- 

 vetch, lupines and pea-vines. 



This orange imitation of the clouded sulphur 

 appears in many forms, each succeeding brood 

 of the year being a different shade of yellow from 

 the others, except in the far South, where it seems 

 to have reached its limit in depth of color after 

 the third brood. In some of the later broods 



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