70 BULLETIN 826, U. S. DEPARTMENT OF AGRICULTURE. 



In some respects the genus is suggestive of Anoecia, although it 

 seems to be undoubtedly a Pemphiginid and will no doubt be so 

 proven by the sexual forms. 



In 1917 Matsumura .erected his genus Watabura with Watabura 

 nisMyae Mats, as type. This species was stated to resemble a Pem- 

 phigus, excepting that the antennal segments are somewhat different 

 and only one oblique vein is in the hind wing. (Two obliques are 

 shown in his PL XII, 9). The antennae are armed with narrow trans- 

 verse sensoria and there seems little doubt that this genus is a syno- 

 nym of Dryopeia. It is noteworthy that the life history of the type 

 species is not known, but it is thought to live on the roots of trees. 

 The type of the genus Dryopeia is a root feeder. 



Characters. — Cornicles present, situated on broad shallow cones, suggestive of those 

 of Anoecia. Stem mother unknown, apterous forms with six-segmented antennae. 

 Alate forms with six-segmented antennae, armed with narrow transverse sensoria. 

 Fore wings with media simple, hind wings with one oblique vein. Summer forms 

 subterranean, living on the roots of plants. Spring forms and sexes unknown. Apter- 

 ous tarsi one-segmented. 



Type (fixed by Kirkaldy, 1906), Endeis bella Koch. 



Genus MORDWILKOJA Del Guercio. 



Plate XI, A-G. 

 1909. Mordwilkoja Del Guercio, Rivista Patol. Veget., v. 4, p. 11. 



This genus was erected in 1909 for the peculiar species Byrsocrypta 

 vagabunda Walsh. This differs in the antennae quite remarkably 

 from all of the other species belonging to this tribe. The difference 

 is in the long unguis of the sixth segment. However, the other char- 

 acters and the four-segmented nature of the antennae of the stem 

 mother seem to place it with little doubt in the Pemphigini. 



There has been some doubt cast by Oestlund on the determination 

 of Walsh's species and this has led Cockerell to propose the name 

 oestlundi for the species now known so well, but, as Gillette has 

 pointed out, Walsh, evidently accepted the insect of Riley and Monell 

 as the same species as his vagabunda. The insects Riley had were 

 undoubtedly the species we know and the writer therefore accepts 

 vagabunda and the generic name Mordwilkoja. The genus was 

 erected with the name vagabunda used as type and not oestlundi. 



Characters. — Cornicles present as somewhat elevated rings. Stem, mother with four- 

 segmented antennae, the unguis of segment VI slender and Aphis-like. Permanent 

 sensoria ciliate. Alate form with five-segmented antennae which are armed with 

 narrow transverse sensoria. Fore wings with the media simple, hind wings with both 

 media and cubitus present. 



Forms living in galls; the stem mother and her offspring living in the same gall, the 

 alate forms leaving the galls in spring or early summer. Sexes unknown, but no 

 doubt small, apterous, and beakless. 



Type (monotypical), Byrsocrypta vagabunda Walsh. 



