326 I.EPIDOPTERA. 



tends to the costa, and .it its lower edjjfe throws oft" one or two 

 black pointH ; second line obscure, a mere series of grey dots 

 edged by a band of the white ground colour ; this last forms 

 a cross with another white stripe, which bends so as to pro- 

 ceed from the ape.x to the hind margin, and to isolate a black 

 costal spot, and two more such spots, one at the hind margin 

 the uther at the anal angle ; cilia white, dotted with black. 

 Hind wings small, llatly rounded behind, greyish-white, cilia 

 white. Female similar. 



Underside of the fore wings shining pale smoke colour, 

 more yellowish along the costa and hind margin. Hind 

 wings dusky white, with two or three cloudy transv-erse faint 

 strijjes of smoke colour. Body and legs brownish-white, the 

 front tarsi black, with white bars. 



Tolerably constant, its deep black markings on white or 

 sometimes greyish-white ground forming its most reliable 

 characteristic, but occasionally the central black spot is e.t- 

 tended so as almost to form a complete band. 



On the wing from the middle of June till August. 



Lakva. iiody cylindrical, of moderate bulk, and attenu- 

 ated slighty at the e.xtremities ; head and dorsal and anal 

 plates highly polished, very dark bron/.y-brown ; ground 

 colour greenish-yellow, very similar to that of the lichens on 

 which it feeds ; raised dots partially joined, bronzy-brown ; 

 segmental divisions deeply cut ; on each segment is a slight 

 transverse ridge : when it is crawling the dark green alimen- 

 tary vessel shows through the divisions as a dorsal stripe, but 

 there are no perceptible subdorsal or spiracular lines. Ventral 

 surface and prolegs of the colour of the dorsal area. Legs 

 ringed with darker. (G. T. I'orritt.) 



April till the beginning of June, on lichens and mosses 

 growing on the trunks of ash, ai)|ile, and sometimes elm- 

 trees. 



Pupa apparently undescribed. 



