GENERIC CLASSIFICATION OF APHIDIDAE. 75 



are more slender and of somewhat different proportions and the 

 cubitus and anal of the fore wings are united somewhat at base. In 

 other genera, however, this difference between species is to be found, 

 and it seems wisest not to adopt it in this group as of generic im- 

 portance. 



Characters. — Cornicles absent. Antennae of five segments armed with linear or 

 somewhat oval sensoria. Fore wings with the media simple, the stigma normal; hind 

 wings with both media and cubitus present. Sexes unknown. Forms making galls 

 upon the leaves of plants. 



Type (fixed by Matsumura, 1917), Nurudea ibofushi Mats. 



Genus PEMPHIGELLA Tullgren. 



1909. Pemphigclia Tullgren, Arkiv for Zool., v. 5, p. 171. 

 1918. Dasia Van der Goot, Mem. Ind. Mus., v. 6, p. 152. 



Characters. — Cornicles absent. Antennae of six segments armed with oval sensoria. 

 Hind wings with both media and cubitus present. Sexes unknown. Species form- 

 ing galls on plants. Type (monotypical), Tetraneura cornicularia Pass. 



Tribe PROCIPHILINI. 



The tribe Prociphilini contains forms which specialized in some direc- 

 tions more than did the Eriosomatini. In other ways, however, they 

 appear to be more primitive than certain genera of that tribe. The 

 cornicles have here disappeared altogether and large wax areas have 

 replaced them. In their habits of gall formation, however, the 

 Eriosomatini are more advanced than are members of the present 

 tribe. 



Characters. — Forms living in crumpled or twisted leaves or in a somewhat complete 

 gall caused by the rolling up of the leaves of the host. Wax plates present; cornicles 

 absent; antenna? of stem mother of five segments; those of the alate form six segmented 

 and armed with narrow, transverse, or somewhat broadly oval sensoria. 



Key to the Genera op the Prociphilini. 



1. Media once forked, stem mother usually without wax plates Asiphum. 



Media simple, stem mother with several rows of wax plates 2. 



2. Wax plates large, those on the thorax well developed, stem mother and 



offspring living together. 3. 



Wax plates not well developed, stem mother usually in a gall by herself . . Thecabius. 



3. Sensoria narrow, linear, ciliate 1 Prociphilus. 



Sensoria somewhat oval, nonciliate Neoprociphilus. 



Genus ASIPHUM Koch. 



Plate XII, R-X. 

 1857. Asiphum Koch, Die Pflanzenlause Aphiden, p. 246. 

 1859. Type fixation, Gerstaecker, Berieht for 1857, p. 249. 

 1905. Type fixation, Kirkaldy, Can. Ent., v. 37, p. 418. 



The genus Asiphum was erected by Koch with two species, populi 

 Fab. and ligustrinellum Koch. He listed De Geer's work in the 

 literature under populi Fab. The populi of Fabricius proves to be 

 the tremulae of De Geer. Only the species ligustrinellum was placed 



