HEMICHEOA RUFA. 7 



discovered, by Mr. J. E. Fletcher, who was fortunate 

 enough to rear a few specimens. That gentleman 

 (E.M.M., xviii, 126) induced virgin females to deposit 

 eggs and reared males and females from them ; and I 

 have myself reared females from unfertilized eggs. 

 The $ can scarcely be distinguished from that of 

 alni ; with the limited materials in my possession I 

 have not been able to find any satisfactory characters 

 whereby they can be separated. The wings vary in 

 the intensity of the smoky tints, some specimens 

 having them almost hyaline, and not darker at base 

 than at apex. 



E. unicolor, Rudow (S. E. Z., xxx, 218), I take to 

 be a variety of this species, wanting the black on the 

 legs and metanotum. 



The larva is found on birch and alder. Five or six 

 eggs are deposited in a leaf stalk, indifferently on 

 either side. When young the head of the larva is of a 

 shining pale brown, the intensity of which varies ; eye- 

 spots black ; the rest of the body is pale green, save a 

 black narrow stripe going down along the side over 

 the spiracles ; the second segment is pale yellow. 



When full-fed the head is shining black, bearing a 

 few pale hairs, and the mouth is pale. The second seg- 

 ment is pale orange, the rest greyish green. Above the 

 spiracles is a black line, which extends to the pe- 

 nultimate segment. Over the legs are two black dots, 

 separated from each other, and forming two bands. 

 On each segment (especially noticeable on the back) 

 are (in front) two tubercles, and behind these other 

 four, each ending in a minute hair.. The legs are 

 greenish white, and before each is a v-shaped black 

 mark ; claws brown : the claspers are whitish. The 

 last abdominal segments are paler than the rest. 

 Cteniscus lituratorius, L., is its parasite. 



Unlike the larvas of H. alni, six or seven of those of 

 rufa live together on a single leaf, eating along the 

 edge, or more rarely in the centre. As they increase 

 in size, however, they are not so gregarious, especially 



