KORTUUMBERLAND AND DUUIiAM. 109 



This, the most interesting of our local Butterflies, was first 

 met with in England by the late William Backhouse, Esq., in 

 Castle Eden Dene, about thirty-fi\te years ago, and it is only 

 known at present to frequent a very few localities in some of 

 the Yorkshire and Lancashire dales. In Scotland it is more 

 generally diffused. In 1829 I first had the pleasure of capturing 

 it in the above locality, Avhere it abounds, in the early part of 

 August, in the more open grassy places in the dene. The num- 

 ber and distinctness of the ocelli vary a good deal, especially in 

 the males. With regard to its variations, I have observed else- 

 where,* "that the males never have the broad brown band under- 

 neath the posterior wings, instead of the blueish-ash one, whilst 

 the females may be considered as divided into two great varieties 

 (equally common), distinguishable not only by the colour of that 

 fascia, but by the greater distinctness of the ocelli, which, in the 

 variety n of Stephens (that with the blueish-ash fascia, which I 

 conceive should have been the typical one), are rather obscure, 

 and approach, in appearance, those of the males." This year, 

 1857, I captured a female, having the rufous on the fascia of the 

 iipperside of the anterior wings, in which are the ocelli, replaced 

 by very pale luteous, almost white. It was reported, some 

 twenty years ago, that its congener, JE. Cassiojie, had been taken 

 in the dene,, but this is very nnlikely, as that species only occurs 

 on mountain sides at from 1500 to 2000 feet of elevation in our 

 latitude (55 degrees), and at quite a different season of the year. 

 Such a report might originate in the capture of some very small 

 specimen, for I once met with one, a male, not larger than the 

 usual size of Cassiope. 



The larva has never been figured, and but seldom seen. This 

 year, for the first time, I have succeeded in obtaining a few eggs, 

 which hatched about fourteen days after they were deposited, 

 and the larvse are now (October) feeding freely on several species 

 of Poa. They have undergone their second moult, and may be 

 described as pale green, with a dark green or brownish stripe 

 down the back, and two white ones, narrowly bordered by the 

 same dark colour, on each side. In the lower white stripe on 



* £nt. 31ug. vol. i., p. 41, 18.^2. 



