2o6 LEPIDOPTERA. 



Rather variable in the ground colour, from whitish to pale 

 brownish-grey or pale slate-colour ; and also in the depth of 

 colour of the transverse stripes. Mr. S. J. Capper has an 

 exquisite specimen, taken in Yorkshire, in which they are of 

 a very rich dark purple-brown, the base equally dark, liaving 

 also two additional purplish stripes, and two of an orange- 

 yellow, the remaining surface being clouded with grey ; 

 another, from the New Forest, in the same collection, is 

 pinkish-white with one broad and one narrow stripe ; in that 

 of the late Mr. H. Doubleday is one of an almost unicolorous 

 slate-grey ; Dr. Mason has similar specimens, and others with 

 the middle of the wings suffused with grey ; but all these 

 extreme forms are rare. 



On the wing in September, sometimes at the end of 

 August. 



Larva plump, almost fat, but flattened above and below, 

 smaller at the extremities, naked ; head narrow, rounded 

 above, blackish-brown ; body pale purplish-grey or greenish- 

 grey, tinged with yellowish above, and with a slender dark grey 

 dorsal line, and more slender grey spiracular lines dotted on 

 each segment with black ; spiracles black ; feet greyish-white. 



April to June on oak, concealed in the daytime between 

 spun-together leaves ; coming out at night to feed. Difficult 

 to disturb from its hiding-place during the day, and, for so 

 common a species, very seldom observed. 



Pupa rather slender, abdomen conical, spine very slender 

 and delicate ; surface rather dull ; reddish-brown ; in a slight 

 cocoon among leaves. 



The moth is said to sit, sometimes, on tree trunks, but is 

 not often so observed ; probably it usually hides during the 

 day in oak trees among the leaves. It flies at dusk and comes 

 very freely to sugar spread on the oak trunks, sitting down 

 cjuietly with closed wings to feed, and allowing itself to be 

 captured with the greatest ease. Sometimes it may be thus 

 secured before dark and without the aid of a lantern. 



Principally confined to oak woods, and common in most of 



