234 



INSECTS INJURIOUS TO THE GRAPE. 



less succulent, the lice seek other quarters, and many of them 

 find their way to the roots of the vines and establish them- 

 selves on the smaller rootlets. By the end of September the 

 galls are usually deserted. In Fig. 241 we have this type 



FIG. 241. 



of the insect illustrated : a shows a front view of the young 

 louse, and 6 a back view of the same, c the egg, d a section 

 of one of the galls, e a swollen tendril, /, g, A, mature egg- 

 bearing gall-lice, lateral, dorsal, and ventral views, i antennae, 

 andy the two-jointed tarsus. 



When on the roots, the lice subsist also by suction, and their 

 punctures result in abnormal swellings on the young rootlets, 

 as shown at a in Fig. 242. These eventually decay, and this 

 decay is not confined to the swollen portions, but involves the 

 adjacent tissue, and thus the insects are induced to betake 

 themselves to fresh portions of the living roots, until at last 

 the larger ones become involved, and they, too, literally waste 

 away. 



In Fig. 242 we have the root-inhabiting type, Radidcola, 

 illustrated: a, roots of Clinton vine, showing swellings; 6, 

 young louse, as it appears when hibernating ; c, d, antennae 

 and leg of same ; e, f, g, represent the more mature lice. 



