SUBFAMILY APHINAE 99 
. Alate Vivipara. Head and thorax brown; abdomen bright green; appendages dusky brown. 
Measurements same as aptera or slightly larger. Hairs spinelike; .10 long on hind tibia. Ros- 
tral IV+-V .12-.13 barely attaining 2d coxa. 
Dimorph. Pale green; without dark markings. Mosaic pattern consisting only of a pair 
of median dorsal plates on each segment from pronotum to tip of abdomen; remainder of 
dorsum rugose. Armed with flabellate hairs along margins as follows: Four on vertex, two on 
antennal I, and one on each segment posterior to pronotum; flabella somewhat pointed, the 
pair on the tip of the abdomen quite slender. Body length .50-.70; hind tibia .13; antenna .37- 
.40. 
Dimolt (Adult Developed from Dimorph). Same as apterous summer vivipara except 
smaller. Body length 1.6; hind tibia .60; antenna 1.0, III+-IV (coalesced) .36, V .13, VI .10 
+ .20. 
Ovipara. Apterous. Head and prothorax dark brown; remainder of body dark olive-green, 
pale around cornicle bases; appendages sordid to dusky especially distally and on hind tibia. 
Cauda and cornicle pale. Body length 2.1; antenna 1.1, III .30, IV .20, V .17, VI .10+.22 
(division between III and IV may be indistinct); hind tibia .70, slightly swollen on proximal 
half and bearing scattered small sensoria over nearly entire length. 
Male. Apterous. Olive-green to brownish. Body length 1-1.35; hind tibia .60-.80; an- 
tenna 1.1-1.2. Hairs as in viviparae. 
R. 
oes ad aN ag 
StS ie EE LO, 
Dimorph =e 
Fig. 107. Periphyllus negundinis 
Collections. On leaves and twigs of Acer negundo and A. pseudoplatanus. 
Generally throughout region. Fundatrices March 12 to May 4, apterous sum- 
mer viviparae May 10 to Oct. 31, alate viviparae May 4 to Sept. 27, oviparae Oct. 
3 to Nov. 16, males Oct. 3 to 15, dimorphs May 4 to Aug. 19; very common. 
Cotypes. Ill. Nat. Hist. Surv. Collection, No. 2775. 
Chief Distinguishing Characters. Immaculate green body, long spinelike 
hairs on appendages, length of unguis (2.5-3 times base) and characters of 
dimorph (especially dorsal plates and length of unguis), and abundance of 
latter form. 
Periphyllus populicolus (Thomas) 
The Cloudy-winged Cottonwood Leaf Aphid 
Chaitophorus populicola Thomas, 1877:10; Essig, 1909c:98. 
Periphyllus populicola, Gillette and Palmer, 1931:924. 
Fundatrix. Rusty brown on head, spreading somewhat onto prothorax, and sometimes 
laterally on mesothorax; abdomen deep apple-green; antennal VI, and tip of V, entire tarsi 
and tips of tibiae black or blackish. Body length 2.5-2.75; antenna about .90, or with III and 
IV fused, total length .75. 
Apterous Vivipara. Head brown; body yellowish or greenish with rather solid mottling 
of brownish, leaving only a pale V-shaped area on dorsum, pale ring about each cornicle and 
pale median area on terminal abdominal segments; cornicle and legs pale. Body length 2-2.5; 
hind tibia .9-1.0, hind tarsal II .16-.19; antenna 1.3. Hairs spinelike on vertex .06-.08 long; 
