Genus Colias. 139 



and have developed a number of constant local varieties, 

 whilst other varieties do not appear to be fixed, and all are 

 much influenced by local conditions. Palceno and its 

 forms are pretty nearly confined to the colder regions of 

 Europe, Asia and America. Edusa takes its place in 

 more southern and warmer regions, though it also has 

 developed arctic forms, like Heda and Boothi. Hyole, with 

 its forms, is confined to the Old World, though its arctic and 

 alpine representative nastes spreads into the northern parts 

 of North America. 



As regards the species in Group I., G. edusa seems to 

 be smallest in Syria and largest and brightest in the South 

 of Europe. 



To Myrmidone, which does not extend to Northern or 

 Western Europe, it is very closely allied. As we go east 

 it develops other forms, such as TMsoa, aurorina, Feildii, 

 and aurora, gradually increasing in brilliancy. 



In South Africa it appears in the form of electra, which 

 though distinguished in the male sex by the tint of the 

 orange, in the female sex may easily be confused with the 

 females of the Himalayan form Feildii. Near this latter 

 there are specimens from Ladak, in the British Museum 

 and in Mr. Moore's collection, difiering considerably from 

 the usual Himalayan form found in Kashmir, Nepal, and 

 Sikkin ; but I should not like to separate them specifically 

 without knowing more about them. 



Another supposed species, difiering from Feildii in its 

 paler colour, and having some slight difi"erence in the 

 discocellular marks, has recently been separated by Moore 

 as C. Stolikczhana, from Ladak, and another from 

 Turkestan has been described as G. Staudlngeri. A 

 female from the Punjaub is very near the Grecian Held- 

 reichl (for the varieties of which consult Staudinger on the 

 Lepidoptera of Greece and of Asia Minor, in Horse Ent. 

 Koss). 



G. aurora, first figured and described by Esper, from 

 specimens sent by Bober from Nertchinsk, and afterwards 

 found at Kiachta on the border of the Gobi desert, and on 

 the Amur river by later travellers, is the brightest in 

 colour of any of the genus, and though, according to 

 my views, only a local race of Edusa, is very easily distin- 

 guished from any of the other varieties, by the extremely 

 bright fiery orange in the wings of fresh males, and 

 as it appears from the figure of Boisduval, in the females 

 also (though I have seen none of this colour). In Mus. 



