MOIST FOREST MARGIN 267 
willow in spring (Fig. 267). Sawfly larvae are common; the large light- 
colored one (Cimbex americana) (179) has habits of special interest. The 
female, which is a wasp-like insect, deposits her eggs on the under sides 
of leaves. Blisters are formed, and a 
young larva lives for a time in each 
Cae Fo 
263 264 
Fic. 263.—The oblong leaf-winged katydid (Amblycorypha oblongifolia); (after 
Forbes) natural size. 
Fic. 264.—The fork-tailed katydid (Scudderia furcata) (after Lugger from 
Forbes); natural size. 
of these. Later it is to be found living freely on the leaves. It usually 
rests with the posterior segments wrapped around a petiole or twig. 
Pupation takes place in a 
silken case. The spotted 
sawfly larva (Pteronus 
ventralis Say) (179) is less 
common. 
Beetles are common 
on the willow. The leaves 
are eaten by May-beetles 
(189) and several leaf-feed- 
ers (Calligrapha and Lina 
are common). Several 
borers attack the twigs 
(Saperda concolor). Galls 
are very numerous. The 
trunks of small willows are 
commonly attacked by the ; : 
dagger-moth (Acronycta oblinita), which feeds upon 
larvae of the introduced ; ; 
various forest-margin weeds and shrubs; natural 
snout-beetle (Cryptorhyn- size (after Riley). 
chus lapathi), and the 
goat-moth larva (Prionoxystus robiniae Peck.), which bores in the heart- 
wood. The sap which exudes attracts many sap-beetles (Nitidulidae). 
