31 6 LEPIDOPTERA. 



with it a form in which the fore wiugs are wholly dark 

 purple-brown, purple-black or slate-black, usually with the 

 stigmata equally suffused or else the reniform is a shade 

 paler. These dark forms are common in South Yorkshire, 

 almost to the exclusion of the paler, and mingled with the 

 more typical, are found in various districts farther north. 

 Mr. Percy Bright has a charmingly pretty specimen from 

 Moray, in which the ground colour of the fore wings is deep 

 slate-grey, but the base, the stigmata, and a broad subterminal 

 stripe are soft whitish-grey. Another in the same collection 

 is rich dark parple-grey with a black central stripe, and 

 another black stripe near the base, both very straight, and 

 the stigmata edged with pale grey. Shetland examples are 

 pale in the ground colour, but large, and with the markings 

 intensified. 



On the wing from the end of June to the beginning of 

 August. 



Larva elongate, smooth, cylindrical, very slightly tapering 

 to each end ; skin thick ; head rather large, shining, whitish- 

 bone colour ; mouth and the incision between the head and 

 the second segment black ; general colour pale green ; dorsal 

 line broad, white or yellowish-white ; subdorsal line of the 

 same colour, threadlike : spiracular line yellowish or whitish, 

 the lower edge indistinctly defined ; usual raised spots large, 

 whitish and distinct ; incisions of the segments tinged with 

 yellow ; spiracles black ; a black mark in front of the base of 

 each of the legs. (C. Fenn.) Apparently it is not always 

 green. Mr. W. R. Jeffrey has found it of a brown colour ; 

 and curiously enough this brown larva — which fed on aspen 

 — produced an unusual variety of the moth, already alluded 

 to. 



March to June, on sallow, especially Sali:): ca])ra:a and 

 »S^. cinerca. and more rarely on poplar, willow, osier, aspen 

 and even hawthorn ; when young drawing together the 

 opening shoots with silk and feeding within, when more 



