RIPERSIA. 183 



less compact ovisacs, within which the female encloses 

 itself, the largest known ovisac being that of R. 

 tomlinii, Newst. (PI. LXVIII, fig. 1). 



More than thirty species have been recorded from 

 various parts of the world, including Europe, North 

 Africa, New Zealand, Australia, and North America. 

 Nearly all the species have been found associated with 

 ants, chiefly of the genera Lasius and Tetramorium. 

 According to Mr. Smith's observations on the New 

 Zealand coccids found associated with ants, the latter 

 almost invariably establish their nests on sites already 

 occupied by root-feeding coccids. Some species of ants 

 manifest the greatest care for the coccids, while others 

 have, apparently, little regard for them. In Vol. I, 

 p. 21,1 have already called attention to the interdepen- 

 dence of these insects, and referred to Mr. Smith's 

 paper ; and I have also added hereafter some informa- 

 tion on the British species. 



SYNOPSIS OF SPECIES. 



A. Anal lobes of adult female very small or rudi- 



mentary. 

 a. Ovisac with long, radiating, iridescent filaments. 



(i) .... FILICICOLA. 



I). Ovisac somewhat pyriform, felted. 



(n) .... TOMLINII. 



c. No definite ovisac. 



(ill) . . . SUBTEERANEA. 



B. Anal lobes of adult females large, chitinised. 



a. Antennas of adult female with five joints. 



(iv) .... TEKRESTRIS. 



b. Antennas of adult female with six joints. 



(v) .... HALOPHILA. 



