THE ELM-LEAF BEETLE IN NEW YORK STATE lY 



this bark-louse for a few years begin to die, the tree itself shows 

 signs of weakness, and when it is attacked by both the elm-leaf 

 beetle and this bark-louse its destruction follows in a few years. 



Fig. 3 —Females of Gossyparia ulmi (slightly enlarged) 



Description and life-history. The adult females are very 

 conspicuous- and may be found on the under side of the smaller 

 branches, frequently clustered in masses and appearing not un- 

 like certain lichens. Each at this time is about j\ inch long, 

 oval in outline, with the extremities slightly pointed, and if 

 crushed causes a reddish stain from the contained ova. The 

 body is surrounded with a mass of white, woolly secretion and 

 the segmentation is also indicated by the same substance, as 

 shown in the accompanying figure. The minute yellow young 

 make their appearance early in July and soon settle for a time on 

 the greener twigs and along the principal veins of the leaves. 

 In the autumn the back of the partly grown bark-louse is covered 

 with spiny processes secreting a white waxy matter. At this 

 time most of the insects forsake the leaves and settle for the 

 winter in crevices of the bark. In the early spring the females 



