174 



INSECT.'^ IXFESTTNG THE GRAPE. 



lice are working; c a root which thev liave rlepcrted ; r/. r/, d, 

 (l.Xhi? lioo on large roots: r. the female ])U]ia. back view — 

 color, yellowish: /'. tlif same, ventral view: (j. the winged 

 female, hack view — color, yellow : //.the same, ventral view; 

 /. her antennie, more highly magnified : ,/, side view of wing- 

 less female, layiiig eggs : /.-. a section of an infested root, show- 

 ing eflects of their work. 



Fig. 152. 



In discussing the merits of fertilization, vine-growers have 

 used 1h<' f.dlowing argument : " \^ fertilizers are usctl t<i pro- 

 duce a vigorous growth ()f the vine, so as to offset the damage 



