128 



A.V ECONOAIIC ENTOMOLOGY, 



for their distribution. As they never come to the surface, so far 

 as we know, they are never winged, and are usually dull white 

 in color, or with a slight tinge of green. The body is covered 

 with a whitish powder and lacks honey-tubes. 



Fig. 94. 



Phylloxera vastatrix.—a. unaffected rootlet of grape; b, rootlets with newly-formed 

 galls; c, same, with old and dried-up tissue; dd, groups of the lice on roots and root- 

 lets ; e,f, female pupa, from above and below; g, h, winged females; i, an antenna; j, 

 oviparous wingless female and her eggs ; k, root showing location of the eggs. 



An advance upon those root-living species is found in Phyl- 

 loxera, which belongs with Chermes in a sub-family, Chermesma, 



