SUBFAMILY APHINAE 95 
AROStCAIBUV + Vine ls-.20) longer than: unpulse( Pa Le) cee ces-c-c.ste cess: oad eeee ee ce ee utahensis 
memeerostral) bV-+- Vul(al2-.14), motlonger than tunel Siete cer ear. nec ee ees eae eee eae 5 
SUE us tal-o tines paserOleV.L. wings hyaline: (p..96) 2.5 oes eee tne brevis pinosus 
Unguis at least twice as long as base of VI; wings hyaline (p. 101).................... saliciniger 
.. Unguis hardly twice as long as base of VI; wings with veins heavily bordered.................. 8 
6. Unguis ADOUtESELIIMESFa SHON eaSeDASEHO Lm Vile Corel O 2) ) setae eee eee een ee testudo 
Unguis shorter than 3 times base of VI............-:::cscsscseccssssseseseseeees OER Ein, Se en ER ned ae 7 
Pee LNeNisrateleast 4etimiesrDaSe 1Ol VLC pO 1) sececessee ete serge eee ne eee ee ae lyropictus 
7. Unguis hardly longer than twice base of VI (p. 98)............2.2:::ccc0eeccccececeeceecceeeeeeeeeeeee negundinis 
Winruisec-suttmesolenothyOr DaSe Of Vil (p05) ce tecsescce seer re cee eee cece eee oe oe eee americanus 
...Unguis shorter than 2 times length of base of VI (p. 96)...............2..ceeccseeeeeeeeeees brevispinosus 
Seb odyadarkeprown <togblacl: (69,7) acess tates ee ce ees we ED oe eye bruneri 
Bodt green and brown .(pA99)s2.caee teeth ee TF ls bcsiv ce od lu bench oben ee populicolus 
Periphyllus americanus (Baker) 
The American Maple Aphid 
Chaitophorus americanus Baker, 1917a:428 and 1918:86. 
Periphyllus palmerae Knowlton, 1947b:24. 
Apterous Summer Vivipara. ‘‘Pale yellowish green with dark median stripe on abdomen 
forming a cross in the region of the cornicles.”’** (Cleared and mounted on slide), pale through- 
out except tarsi and tips of III, IV and V and entire VI which are dark. Body length about 2; 
hind tibia .80-1.1; hind tarsal II .16; antenna 1.64-1.85; rostrum attaining 2d coxa. Hairs 
spinelike on body, .13-.20 long. Cornicle with broadened base, approximately cylindrical and 
reticulated on distal half. 
Fig. 103. Periphyllus americanus 
Alate Vivipara. (Cleared and mounted in balsam), head, thorax, antenna, cornicle and 
legs beyond proximal portion of femora blackish; abdomen pale with dark lateral areas and 
dorsal bands, the latter frequently broken on median line. Body length 1.4-2; across eyes 
.49-.55; hind tibia 1.2-1.4; antenna 1.4-2.14; rostrum attaining lst-2d coxa. Hairs on body 
spinelike, curved, .10-.15 long. 
Dimorph. “Pale green’; without dark markings. Body length .45-.50; across eyes .19-.20; 
antenna .45-.50; hind tibia .13-.14; hind tarsal II .06. Body flat and armed with flabella in 
place of simple hairs, situated as follows: 2 on vertex, 2 on antennal I, one (much narrowed 
and reduced) on lateral margin of prothorax (near posterior suture), one somewhat narrowed 
on mesothorax, one (.06 by .04) on lateral margin of each su>sequent body segment, totaling 
11 on each side; with a pair of shaftlike or greatly narrowed flabellate hairs .06 long on tip of 
abdomen. Antennal I with double protuberance on anterior margin forming bases of hairs. 
First and second tibiae bearing flabellate hairs on outer margin, hind tibia with simple hairs. 
Cornicle not evident. Dorsal plates visible only as a pair on median line on meso- and meta- 
thorax and abdominal I and II, rather dim. 
Apterous Fall Vivipara. (Perhaps dimolt). (Mounted in balsam), without dark markings. 
Body length 1.70-2; across eyes .45-.50; hind tibia .65-.80; hind tarsal II .12; antenna about 
1.0, III .33 (imperfectly divided), IV .15 (III+IV fused .43), V .15, VI .10+.22; rostral 
IV+V .12, attaining 2d coxa. Hairs as in apterous summer vivipara. 
Collections. On Acer grandidentatum, A. saccharum, A. saccharinum, A. 
pseudoplatanus and A. glabrum, on leaves. Colorado: Grand Junction. Utah: 
*According to Hottes in correspondence. 
