on the genus Colias. 13 



tinct, though not easy to make out ; and I am still 

 without further knowledge of this curious form. 



Colias Leshia, Fabr. 



Since writing on this species I have gathered a good 

 deal more information as to its distribution, which is 

 much wider than I at first supposed. 



Berg, in Bull. Mosc, 1876, p. 198, records it as com- 

 mon in Patagonia, from Eio Negro to Santa Cruz, and 

 it is the commonest of butterflies in the Argentine States 

 as far N.W. as Sierra de Potoral, Prov. Catamarca 

 (White) ; occurs at Rio Grande do Sul, in South Brazil 

 (Rogers) ; and at various localities in the Andes of 

 Ecuador, where Mr. Whymper found it in some numbers 

 at Otovalo and Machachi, 8000—12,000 ft., together with 

 C. dimera, which was more numerous. These Andean 

 specimens agree very well with those from Buenos 

 Ayres, but the females do not seem to be dimorphic as 

 in the south, where the pale form is common. 



Darwin, in his ' Naturalist's Voyage,' mentions the 

 occurrence of a flight of this species containing countless 

 numbers which came on board his ship, ten miles from 

 land, in the Bay of San Bias. 



C. Eogene, Feld. 

 Feld., Reise Novara, p. 196, pi. 27, fig. 7. 



C. Theia, Stgr., MSS. Cat., 1882. 



Var. ? C. Stoliczkana, Moore, Ann. & Mag. Nat. Hist., 

 1878, p. 229 ; Yarkand Exp. Lep., pi. i., fig. 1, 

 1879. 



When I first wrote on Colias I did not know this 

 species so well as I now do, and placed it doubtfully as 

 a variety of FielcUi. This it certainly is not; and having 

 seen the types in the Felder collection, and several other 

 specimens, of which four males and two females are now 

 in my own collection, I believe it to be as good a species as 

 any other in this group, and allied most nearly to Tliisoa. 

 It may be known by the extremely bright fiery orange 

 tint of the upper side, which in the female is much 

 overlaid with smoky black, especially on the hind wings; 

 by the broad black border on both fore and hind wings ; 

 the large red blotch in centre of hind wings, especially 

 in the female ; and the peculiar shape of the costa of 



