SUBFAMILY ERIOSOMATINAE 371 
Alate Fundatrigenia. Head and thorax black; abdomen deep green to black; powdery; 
rostrum and appendages black. Body length 1.8-2.5; hind tibia .80-1.1; hind tarsal II .20-.25; 
antenna 1,03-1.15; fore wing 3-3.3; hamuli 4 in number; rostrum attaining between Ist and 2d 
coxae. Wax plates as follows: one small pair on posterior dorsal portion of head and an 
elongate vestigial pair on edge of mesothoracic lobes. 
Hibernating Apterous Vivipara. (On Ranunculus sp.) Body length 2.1-2.3; hind tibia 
.55-.80; hind tarsal II .20-.25; antenna .91-1.14. 
Spring Apterous Vivipara (on Ranunculus sp.). Body length 1.8-2; hind tibia .50; hind 
tarsal II .17-.19; antenna .63-.72. 
Alate Sexupara (on Ranunculus). Body length 2.1-2.3; fore wing 3.1-3.6 otherwise as in 
alate fundatrigenia except antenna as figured. 
Pseudo Galls. Fundatrix solitary in leaf margin folded on underside; progeny living in 
colonies on underside of younger leaves folded under on midrib. 
MIMD 
20) (sen.2-9 “/8~.22) 
(Sen. 
’ y ey 
p : 
16=: 17+. 19) 104 
Oa (.16-.20) ee ee 
(Sen, 13-18) (eee) (Sen, 0-3) 
Fig. 448. Thecabius populi-conduplifolius 
Collections. As winter host, in folded leaves of Populus “balsamifera” 
(probably P. candicans or P. deltoides) and P. sargenti as summer host on leaf 
bases of Ranunculus sp. Wyoming: Wheatland. Throughout Colorado and Utah. 
Fundatrices June 2 to 25, alate fundatrigeniae June 12 to Aug. 7 and alate sexu- 
parae Sept. 21, apterous viviparae on Ranunculus Jan. 2 to April 23, alate vivi- 
parae Sept. 13 to Oct. 4; rather common. 
Type. Lost. P. ranunculi Davidson and californicus Davidson, possibly in 
U.S.N.M. 
Chief Distinguishing Characters. Folded leaf pseudo gall, rather weak nar- 
row-transverse but not annulated sensoria and presence of 5 or more secondary 
sensoria on VI of fundatrigenia. 
This species is very close to T. affinis and is indeed considered inseparable 
by Mordvilko (op. cit.). However, Mordvilko’s description disagrees with de- 
scriptions and specimens by Tullgren, van der Goot and Theobald in the same 
way that the Colorado specimens differ, namely, No. 3 given above. 
Special acknowledgements are due to Maxson, who cooperated in giving 
information acquired in experimental transfers from Populus to Ranunculus 
and to Davis (the latter loaned a specimen of T. affinis rec2ived from Tullgren). 
Thecabius populi-monilis (Riley) 
Beadlike Cottonwood Gall Aphid 
Pemphigus populi-monilis Riley, 1879:13. 
Thecabius populi-monilis, Gillette, 1913:845; Gillette and Palmer, 1934:235, 
Fundatrix. Dull yellowish olive-green, dark brown on head; powdery, giving appearance 
of slaty-gray; head, rostrum and appendages blackish. Body 3.50 by 2.25; antenna .52; hind 
tibia .45; hind tarsal II .13-.15. Wax gland plates evident, when cleared and mounted, 4 on 
head (not apparent in all cases) and 6 longitudinal rows on body. 
Apterous Fundatrigenia. Light cinnamon; head, rostrum and appendages dusky. Body 
3 by 1.9; hind tibia .45-.50; hind tarsal II .13-.15; antenna .60. 
Late Apterous Virgogenia. Head slightly dusky, body orange-yellow; appendages yellow 
to slightly dusky. Body length 1.8; hind tibia .35-.38; hind tarsal II .10-.13; antenna .38. 
Alate Fundatrigenia. (Mounted in balsam), head, thorax, appendages dusky; posterior 
edge of stigma often darker. Body length 2.75-3; hind tibia .85-1; antenna .85-.90; fore wing 
4-5; hamuli 2-5 in number. Rostrum attaining between lst and 2d coxae. Wax gland plates 
not apparent in specimens cleared and mounted in balsam. 
