SUBFAMILY ERIOSOMATINAE 361 
Alate Vivipara. Fundatrigenia). Head and thorax dark; abdomen pale green to gray- 
green, with dark markings and lateral spots; mealy and flocculent. Body length 1.7-2.2; fore 
wing 2.5-2.6; hind tibia .50-.72; hind tarsal II .15-.18; antenna .60-.75; rostral IV+V .08, at- 
taining 2d coxa.. Wax plates present. Hairs in both forms inconspicuous. 
Hosts. As winter host in petiole galls on Populus sp.; as summer hosts on 
lambsquarters (Chenopodium sp.), carrot (Daucus sp.), lettuce (Lactuca sp.), 
Lampsana communis and Sonchus sp., on roots. (Not recorded from region.) 
Data for descriptions and drawings from Tullgren (op. cit.) and from speci- 
mens determined by van der Goot. | 
Pemphigus junctisensoriatus Maxson 
The Poplar Petiole-leaf Gall Aphid 
Pemphigus junctisensoriatus Maxson, 1934:34; Gillette and Palmer, 1934:223. 
Fundatrix. Pale yellowish white, brownish on head; tibiae brownish. Body length 3-4; 
hind tibia .52-.60; hind tarsal II .15-.16; antenna .47-.50, four- scemented. rostral IV+ V .11, 
attaining 2d coxa. Wax gland plates typical; cornicle absent. 
| a Galls 
SX | oe .20) a ge aah 
f Ny a Viv. (sen.4-5) Gen. 2-# (ser.3-5) 
a A Le COA ps 
\ = (23-29) (Sen 10-15)(09~-10)(.10=12)(.14--.19) + (,03-04) 
Fig. 433. Pemphigus junctisensoriatus 
Alate Vivipara. Fundatrigenia. Head and thorax blackish; abdomen yellow-green. or 
with bluish tinge; powdery; appendages dusky. Body length 1.4-1.8; across eyes .41; fore 
wing 2.5-3; hamuli 2 in number; antenna .75-.82, secondary sensoria broad and flat, promin- 
ently raised often pastly or wholly anastomosed, not entirely encircling the segments; rostral 
IV+-V .10, attaining between Ist and 2d coxae. Cornicle a mere pore. 
Gall. Pale yellowish green. Composed mostly of swollen petiole; twisted on broadened 
leaf base; exit hole consisting of a crevice extending over halfway around between petiole 
and leaf. 
Collections. On Populus sargenti in petiole and leaf galls. Colorado: Wig- 
gins and Boulder. Fundatrices and alate viviparae (fundatrigeniae) June 8 and 
29, alate viviparae and sexuparae Sept. 2; rare. 
Type. U.S.N.M., No. 50063. Paratypes, Maxson Collection. 
This species is peculiar in the broad and occasionally anastomosed sensoria 
as well as the gall which consists mostly of enlarged petiole with exit hole in the 
form of a long slit between petiole and leaf. 
a Lao x 
Pemphigus monophagus Maxson 
Pemphigus monophagus Maxson, 1934:37; Gillette and: Palmer, 1934:224. 
Fundatrix. Honey-yellow to pale olive-green; brown on head; appendages brown. Body 
length 1.1-1.7; hind tibia .20-.33; hind tarsal II .08-.10; antenna .20-.28, four-segmented ; 
rostrum attaining 2d coxa. Cornicle not evident. Wax plates present except on head. 
Sola" pores Hind Tarsus Ne 
CC “(Sos alata —-se” 
(06-08)(060t02 .08 (12-19) ; = ga 
peer Apt. Viv. = 
} = 08104 
Alate viy 
Me 06-08), 06-083 (11-13) +.03 i ot A pee 
Fig. 434. bempliitis monophagus 
Apterous Vivipara. Whitish to creamy; brownish on head; appendages brownish. Body 
length 1.2-1.44; hind tibia .25; hind tarsal II .10-.11; antenna .39-.46; rostrum as in fundatrix. 
Alate Vivipara. Sexupara. Head and thorax blackish; abdomen pale yellow-green; 
powdery; appendages dusky. Body length 1.4-1.9; hind tibia .50-.74; hind tarsal II .12-.19; 
antenna .48-.58; rostrum attaining between Ist and 2d coxae; fore wing 3. 
Ovipara. Apterous. Body length 1.016; antenna four-jointed .155, I .026, II .026, III+IV 
+V (coalesced) .034 with permanent sensorium near distal end, VI .069 with permanent sen- 
sorium at base of unguis. Rostrum lacking. Tarsi well developed. 
