77 



The Variation of Erebia aethiops. 



By J. W. TuTT, F.E.S. Read Sept. \2th, 1895. 



My interest in Erebia cBthiops dates back to 1884, when I was 

 generously supplied with a large number of larvse by the collectors 

 living at Galashiels, who, I believe, obtained them by sweeping at 

 night the grassy spots which they frequent in that neighbourhood. 

 From these I bred, during July of that year, a long series of imagines, 

 and I still possess eighteen specimens of that particular batch in my 

 cabinet. Looking at those specimens now, they strike me as being 

 a trifle small, the females distinctly less than the males. Pro- 

 bably this suggests that feeding under artificial conditions was not 

 altogether enjoyed by them. 



Running on through my British specimens, I find I have six 

 specimens from Galashiels captured in 1888. These were sent in 

 response to a request to get me a few of the more striking forms. 

 The normal female is, as is well known, somewhat smoother and 

 less bright than the male, and the transverse band less fulvous. 

 Four of these six are females of a distinctly paler ground-colour, and 

 one has the transverse band of a pale orange, almost yellow, tint. 

 They exhibit, however, a uniformity of size with the only male sent 

 which is very noticeable. 



From Forres I have specimens just a shade larger than the 

 Galashiels examples, the most striking point being the uniformity 

 of size and the smallness of the ocellated spots in both males and 

 females. The females are much paler in colour than the males. 

 Rannoch supplies a long series, averaging a little less in wing- 

 expanse than the Forres specimens, the uniformity of the spotting of 

 the fore- wings— a double ocellated spot with a single one below- 

 being remarkable. A series from Arran shows a larger race, the 

 sexes uniform in size, but the females paler and much more strongly 

 spotted than the males. 



There is now a long series of about seventy specimens, captured 

 by Dr. Chapman and myself in a walk over the hills from Gareloch- 

 head to Cove in August, 1893. These show considerable uniformity 

 in size, the females perhaps having slightly the advantage in average 

 expanse of wing. Like the Forres specimens they cannot be said to 

 be at all strikingly ocellated, the spots of the males being remark- 

 ably uniform and decidedly small, those of the females larger, but 

 rarely exceeding three (with a trace of a fourth) on the fore-wings. 

 The females, however, on the whole, are distinctly richer in ground- 

 colour than those from the other localities. 



I am astonished to find that I possess no English specimens in 

 my series. I have had large numbers through my hands, but do 

 not seem to have retained a single specimen. 



