138 THE coccroAE 



Malva, Brassica, Solanum, Shinus, Chenopodium, 



Rheum, Rosa, Melilotus, Helianthus, Juglans, etc 



citrophilus Claussen. 



cc. Body always with less than twelve pairs of cerari. 

 d. Body with eleven pairs of cerari. 



e. Cerari arranged as follows: pair cephalad of eyes, pair 

 near eyes, pair opposite prothoracic legs, pair opposite 

 mesothoracic spiracles, and seven pairs on abdomen, ce- 

 phalic and thoracic pairs sometimes wanting; each cerarus 

 usually with two ceraran setae; anal setae and anal ring 



setae subequal. California on Cupressus 



cupressicolus Ferris. 



ee. Cerari arranged as follows: four pairs on head and seven 

 pairs on abdomen; two cephalic pairs of cerari with each 

 cerarus with three ceraran setae, other cerari with two; 

 auxiliary setae associated with ultimate and penultimate 

 pairs of cerari only; dorsal setae few and small; anal ring 

 slightly chitinized; anal setae about one-half length of 



anal ring setae. California on Distichlis scainus Ckll. 



dd. Body always with less than eleven pairs of cerari. 



e. Body with eight or nine pairs of cerari counting cephalad 

 from anal cerari and usually with pair cephalad of eyes; 

 cephalic pair on head with several ceraran setae, other 

 cerari with two; anal cerari with auxiliary setae, lateral 

 cerari without; dorsal setae numerous, slender; anal setae 

 about twice as long as anal ring setae. California on 

 Eriogonum, Viola, Stachys, Eriodictyon, Ceanothus, Erig- 



eron. eriogoni Ehrh. 



ee. Body with ten pairs of cerari. 



f. Anal ring setae about equal in length to anal setae and 

 about one and one-half times as long as width of anal 

 ring; head with only ocular cerari, which contain three 

 or four ceraran setae, other cerari with two; auxiliary 

 setae present only among the anal cerari; dorsal setae 

 few and small. New Mexico, Utah, California on 



Gutierrezia. gutierreziae Ckll. 



ff. Anal ring setae somewhat shorter than anal setae; anal 

 setae about one and one-half times as long as width of 

 anal ring; head with only ocular cerari, which contain 

 three or four ceraran setae, other cerari with two; anal 

 cerari only with auxiliary setae; dorsal setae small and 



few in number. New Mexico, Arizona on Prosopis 



prosopidis Ckll. 



Trionymus Berg. This genus contains only two species according 

 to Fernald's Catalogue, perrisii Sign, from France, the type, and a second 

 species, americanus Ckll. from the District of Columbia. Ferris has pre- 

 pared a synopsis of the Californian species. It is possible that several 

 of the species now referred to Pseudococcus belong here. The follow- 

 ing table is based upon the work of Ferris: 



