revision of the genus Argynnis. 567 



A. leto is a species whicli, though undoubtedly nearly 

 allied to cybele, is fully as distinct from it as nokomis, 

 and may be regarded as its Pacific coast form, in the 

 same way as nokomis is the form of the dry central 

 plateau of the continent. Though the male is not very 

 different from the male of cybele, yet the female, which 

 on the upper side is hardly distinguishable from the 

 females of nokomis and nitocris, is marked by the 

 strong contrast between the deep chocolate, almost 

 black, of the base and inner area of the wings and the 

 pale yellowish colour of the outer area. Its range 

 extends along the Pacific coast from Central California 

 to Washington Territory, and it is recorded also by 

 Geddes from Fort Macleod, in the North-western Terri- 

 tory of Canada, on the eastern side of the mountains. 

 Those I have from Washington Territory are considerably 

 darker at the base of the hind wings than others from 

 Plumas County, California ; and I should not be at all 

 surprised if a large series from different localities were 

 to show forms intermediate both with cybele and nokomis. 



A. caiyenteri is unknown to me, except from the 

 description, which seems to point to a form of cybele. 

 It was described from two males and one female taken 

 by Dr. Carpenter in New Mexico at a high elevation 

 above the timber line, and is said by Mr. Edwards to be 

 of the size of atlantis and near cybele. 



A. nokomis and nitocris are regarded by Edwards, in 

 his last catalogue, as distinct ; he cites, however, 

 Strecker's figure of nokomis female, in Piuffner's Eeport, 

 as an aberration of nitocris. This is just one of those 

 cases which prove how difficult it is to follow Edwards's 

 authority in such matters. It so happens that I have 

 two excellent pairs of nokomis from Arizona, sent by 

 Mr. H. Edwards, which exactly agree with Mead's figure 

 cited by Edwards. I have also a pair of nitocris, the 

 male from Utah, sent by Mr. Sfcrecker, the female from 

 Arizona, agreeing with it, is marked by Mr. H.Edwards, 

 "I think this species passes as A. nitocris, female." It 

 differs from nokomis in having the under side of hind 

 wing to the second row of spots cinnamon-colour,' as in 

 cybele, and is exactly intermediate between nokomis and 

 leto. The specimen figured by Strecker in Euffner's 

 Eeport, and cited by Edwards as an aberration of 

 nokomis, is, to my eye, much more like leto than it is to 



TRANS. ENT. SOC. LOND. 1889. PART IV. (DEC.) 2 R 



