52 SYNOPSIS OF 



in a row in company on the underside of the leaf, 

 eating only the cuticle. Cladius viminalis. 



b. Ground colour green, with yellow and black 

 markings, feeding on the edge of the leaf. Throwing 

 off the markings at the last moult ; spinning a single 

 cocoon. Nematus ribesii, N. consobrinus. 



D. Leaf-rolling larvae ; folding down the edge of a 

 leaf, thus forming a covering under which they live, and 

 having anal segments ornamented with black markings. 

 Nematus crassulus, N. bipartitus, Lep., N. nigrolineatus. 



E. Gall-inhabiting larvse. 



a. Living in galls on leaves, 

 i. On willow. 



1. In bean-shaped galls, ranged in numbers along 

 each side of the midrib, and projecting from both sides 

 of the leaf. Nematus gallicola. 



In galls longer than broad, placed in pairs one on 

 each side of the midrib, and projecting more on the 

 upper than on the lower side. Nematus ischnocerus. 



In large oval galls with a considerable internal 

 cavity. Nematus vesicator. 



2. In pea-shaped galls, attached by only a small part 

 of their surface to the midrib and not at all to the 

 blades. 



Galls smooth, shining, glabrous, generally with 

 pink or reddish cheeks ; larva changing colour at the 

 last moult. N. viminalis, N. herbacece. 



Galls green, without red, and covered with longish 

 hair. N. viminalis, N. baccarum. 



ii. In pea-shaped galls on Paccinium vitis-idcea. N. 

 vacciniellus. 



b. In galls on twigs of willows or poplars. 



i. In large irregular galls on the twigs. Crypto- 

 campus pentandrce. 



ii. In the pith of the young twigs. Cryptocampus 

 saliceti, C. angustus. 



III. With eighteen (rarely twenty) legs. Spinning 

 a double cocoon, the outer elastic and reticulated. 



A. The skin covered with stiff hairs, each issuing 



