Genus Colias 
not form as high a keel-shaped projection from the ventral side 
as in that genus. 
This genus is very extensive, being represented throughout 
the temperate regions of both hemispheres, and also occurring in 
the cooler portions of South America, especially along the ranges 
of the Andes. One species is found in temperate South Africa. 
The brightly colored butterflies, which are sometimes found con¬ 
gregating in immense numbers in moist places, are familiar ob¬ 
jects, and swarm upon the clover-fields and by the roadside in the 
summer months throughout the United States. 
(1) Colias meadi, Edwards, Plate XXXVI, Fig. 5, $ ; Fig. 
6, $ (Mead’s Sulphur). 
Butterfly. —The wings on the upper side are orange, greenish 
on the under side. The discal spot on the lower side is centered 
with green. Expanse, 1.75 inch. 
Early Stages. —The life-history has been written by Edwards, 
and may be found in the pages of the “ Canadian Entomologist,” 
vol. xxi, p. 41. The larva feeds on clover. 
The species is alpine in its habits, and is found in Colorado 
from nine to twelve thousand feet above sea-level. 
(2) Colias elis, Strecker, Plate XXXVI, Fig. 13, $ ; Fig. 14, 
$ (Strecker’s Sulphur). 
Butterfly. —This species is discriminated from the preceding 
principally by the narrower black margins on the wings of the 
male and the more abundant yellow maculation of the borders in 
the female. Expanse, 1.55-1.90 inch. 
Early Stages. —Closely resembling those of the preceding spe¬ 
cies, of which it may be only a varietal form. 
The habitat of the species is on the lofty peaks of the Western 
Cordilleras. 
(3) Colias eurytheme, Boisduval, Plate XLVIII, Fig. 18, ? ; 
Plate XXXIII, Fig. 5, 6 , under side; Plate II, Fig. 1, larva; Plate 
V, Fig. 53, chrysalis (Eurytheme). 
Butterfly. —This species has been made in recent years the 
subject of exhaustive study, and has been discovered to be 
strongly polymorphic — that is to say, liable to great variation. 
Not only does albinism assert itself in the production of white 
forms, but there are many seasonal and climatic forms. We are 
not yet through with our studies, and there is doubtless much 
more to be ascertained. The figures cited above represent the 
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