HYMENOPTERA 895 



Family PAMPHILIID^ 



The Web-spinning and the Leaf-rolling Sawflies 



The common names given above were suggested by the fact that 

 the larvae of some species build nests by tying the leaves of their 

 food plants together with a web of silk, and others build nests by 

 rolling the edge of a leaf and live inside the tube so formed. The larvae 

 of some species are gregarious. The larvas of members of this family 

 have long, seven-jointed antennae, well-developed thoracic legs, but 

 lack abdominal prolegs. 



In the fore wings of the adult (Fig. 1135) vein Sc is preserved as 

 a distinct vein; the free part of vein R2 is wanting; and vein Cu2 is 

 usually preserved, at least as a short spur. In the hind wings vein Sc 

 is more or less distinctly preserved. 



The body of the adult is robust. The posterior margin of the 

 pronotiim is straight or nearly so. The mesonotum is short and 

 never extends much beyond the anterior margins of the tegulas. The 

 anterior tibice are armed with two apical spurs. The ovipositor of 

 the female is short. 



More than fifty species have been described from America north of 

 Mexico ; but the larvae of only a few of these are known ; among these 

 are the following. 



The plum web-spinning sawfly, Neurotoma inconsptcua. — The lar- 

 vae of this species feed on the foliage of plum and cherry; they are 

 gregarious and form unsightly nests by spinning webs over the 

 leaves ; frequently these webs cover an entire tree. The injury is done 

 in early summer. When full-grown the larvse find their way to the 

 ground, where they pass the remainder of the summer and winter in 

 earthen cells, they transform to pupae in the spring, and the adults 

 emerge in May or June. This pest is controlled by spraying or dusting 

 the infested trees, with lead arsenate. 



The peach sawfly, Pamphtlius persicus. — This pest of the peach 

 is one of the leaf-rolling species. The adults emerge from the ground 

 late in May or early in June and lay their eggs on the leaves; the 

 eggs soon hatch ; each larva cuts a slit in a leaf and then rolls over a 

 portion of the leaf, making a case within which it stays during the 

 daytime, feeding chiefly at night. There is a single generation a year. 

 The larva passes the winter in the ground. The same method of 

 control is used as with the preceding species. 



