98 THE MOTHS OF THE BRITISH ISLES. 



central band is usually more or less complete, but sometimes 

 it is nearly or quite absent above the blackish triangular patch 

 on the inner margin. Occasionally, there is a yellow blotch at 

 the anal angle, and frequently another on the costal area. 

 Still more rarely the whole ground colour is yellow. (Figured on 

 Plate 38, Figs, i $ and 2 $ .) The caterpillar is green, with six 

 white lines along the back, and white stripes along the sides. 

 When young it feeds on the catkins of birch, and afterwards on 

 the foliage. April to early June. (Plate 39, Fig. i.) 



The moth is out in March and April, and on sunny days the 

 males may be seen flying, generally pretty high up, on the lee 

 side of the birch trees growing on heaths ; also in open spaces 

 in or around birch woods. The females rest on the twigs, as 

 also do the males when the sun is obscured. Both sexes have 

 been found sitting on the ground in sunny glades. 



The species is widely distributed over the southern and 

 eastern counties, common in many parts ; but its range extends 

 through England to Durham, and it has been recorded from 

 Wales. Although it does not seem to have been noted in 

 Scotland south of Kincardineshire, it occurs on the east to 

 Moray. Westmeath is the only Irish locality that has so far 

 been mentioned. 



Its distribution abroad extends to East Siberia and Amurland, 



The Light Orange Underwing (Brephos ?tofha). 



Very similar to the last species, but rather smaller in size, and 

 the fore wmgs are much less variegated. The antennae of the 

 male of this species are bipectinated, whilst those of parthenias 

 are finely serrated. (Plate 38, Figs. 4 J and 5 ? .) 



The caterpillar feeds in May and June on aspen, eating the 

 foliage and hiding between two leaves drawn together. The 

 head is greenish or greenish-brown, with three conspicuous 

 black spots. Body, green, olive-green, or reddish ; line along 



