428 LEl'lDOPTERA. 



wings ample, the apex angulated and the hind margin 

 sinuous ; glossy pale smoky-brown ; cilia still more glossy 

 whitish-grey. Female similar, but with thread-like antenna*. 



Underside of the fore wings shining smoke colour, with 

 the costa paler ; hind wings shining smoky-white. Body and 

 legs pale grey-brown, but the tip of the abdomen beneath is 

 ochreous. 



Hardly variable, but in the far north, and especially in 

 Iceland, the ground colour tends more to silvery grey, with 

 the markings as usual. 



On the wing iu June aud Julj\ 



Larva about three-quarters of an inch long and rather 

 slender ; head a little narrower than the second segment, its 

 lobes rounded ; black and glossy, prettily marbled on the 

 lobes with clear white, and having a white streak above the 

 mandibles ; skin soft and velvety, very sparingly clothed 

 with short hairs ; ground colour dull velvety black; two 

 clear, bright, lemon-yellow stripes extend thi-ough the middle 

 of the dorsal area running parallel from the second to the 

 twelfth segment, where they unite, and form one stripe 

 through that and the thirteenth, on this last and on the 

 second their colour is almost white ; an indistinct and in- 

 terrupted series of small white dots, from about the second 

 to the ninth segment indicates each subdorsal line ; spiracular 

 stripes clear bright lemon-yellow ; and below each is a broad 

 interrupted white stripe ; spiracles black ; ventral surface 

 aud prolegs uniformly dull black ; legs also black but highly 

 polished. (G. T. Porritt.) 



May and June on birch ; always resting on the upper 

 side of a leaf and drawing it together with fine silken threads, 

 into a curve, but so open that the pretty larva is quite visible 

 from above. It eats the upper surface and parenchyma of 

 the leaf and then moves to another which it draws together 

 in the same manner. Sometimes several leaves are attached 

 together with the threads. 



