COLIAS IV. 



rax yellow ; legs roseate ; palpi yellow, dark on upper side, roseate at extremity ; 

 antennjB and club roseate. 



Variety A, t?. Upper side pale yellow with a very slight tinge of orange 

 on disk of primaries ; sometimes wholly without orange and then uniform lemon- 

 yellow ; the marginal borders also very pale. (Fig. 7.) 



Female. Expands 1.7 to 2.1 inches. 



Upjier surface yellow, the secondaries having a greenish tint ; disk of prima- 

 ries slightly tinted with orange ; primaries have the marginal border broad, more 

 or less excavated between the nervules and enclosing a macular yellow band, usu- 

 ally complete, although the spot in median interspace is often but faint ; discal sjiot 

 large, black, circular or ovate, and sometimes enclosing a central spot. 



Secondaries have the border abbreviated posteriorly and dilated towards outer 

 angle, there enclosing two or three yellow spots of a band which disappears in the 

 ground color ; discal spot as in male. 



Under side greenish-yellow except at base and on disk of primaries which are 

 deej3 yellow ; discal spot of primaries large with a central white or yellow spot. 



The usual type from California and Texas. 



Variety A, 2. Upper side of primaries bright orange and of secondaries 

 pale orange, both wings much obscured by black scales ; macular band yellow. 

 From Illinois. (Fig. 5.) 



Variety B, 2. Color above greenish-white, the secondaries with a faint yel- 

 low tint ; beneath secondaries and apex of primaries more decidedly yellow ; 

 marked as in the type. From California and Texas. 



Larva unknown. 



Found in the valley of the ]\Iississippi from Nebraska and Illinois to Texas 

 and w'estward to the Pacific, occupying much the same region as Eurytheme, but 

 a23parently less common and more local than that sjaecies. Also occasionally found 

 in the Middle States and Canada. 



My attention was first called to the differences between the two species passing 

 under the name of Eurytheme by Dr. Behr, in 18(35. In a letter then received 

 from him, he says, "These are two good species but have hitherto been considered 

 as one. I am certain either of the two is different from the European Chrysotlieme ;" 

 (of which sj^ecies Dr. Baisduval had considered Eurytheme as probably a variety.) 

 "It is easy enough to characterise the males, but as to the females, I am often at 

 a loss myself; and at the same time the two species are easy to recognize when on 

 the wing." And again in 1808, "I will send you a pair of each of the two CoUas. 

 The difference is about the same as between Edusa and Myrmidone whose repre- 



