Reference. Spencer, 1981: 34. 
2 ors, 2 ori; 3 dc H. salicis (Mai loch) 
Synopsis. Frons twice width of eye, conspicuously 
projecting above eye in profile (fig. 151); orbit 
broad, orbital setulae sparse, reclinate; gena angu- 
lar, deepest in center, slightly over 0.33 height 
of eye, parafacial prominent; ocellar triangle not 
shining; mesonotum weakly shining black, with dc 3 
strong, immediately behind suture; abdomen entirely 
black; squama gray, margin and fringe black; wing 
with costa ending immediately after termination of 
vein R 4+5, last and penultimate sections of M 3+4 
equal; length given by Malloch as 2 mm; (both wings 
now missing in holotype but illustrated by Malloch, 
1913a); male genitalia with aedeagus as in figures 
152, 153. 
Host/Early Stages. Salix sp. Early stages unknown. 
Distribution. Massachusetts; new record: British 
Columbia, Kootenay District, Carbonate Column, 
Columbia River, 2,600 ft, 1 m. , 7. VII. 12.08 
(J. C. Bradley, CUI) . 
References. Malloch, 1913a: 314; part 2, p. 249. 
5 (1). Last section of vein M 3+4 longer than penultimate 
H. websteri (Malloch) 
Synopsis. Large species, wing length 3.5 mm; frons 
almost twice width of eye; normally 5 orbital 
bristles (rarely 6); gena 0.25 height of eye; meso- 
notum moderately shining black, 3 strong dc, some- 
times small further ones in same line that 
are distinctly stronger than acr; squama gray, 
margin black, fringe blackish; male genitalia 
illustrated by Sasakawa (1961: fig. 35). 
Host/Early Stages. Wistaria spp. Posterior spira- 
cles of larva each with 3 minute bulbs; galls found 
at base of twig buds (fig. 154). 
Distribution. Washington (introduced); Japan. 
References. Malloch, 1913a: 325; Sasakawa, 1961: 
353. 
— Last section of M 3+4 shorter than penultimate 6 
6 (5). Last section of vein M 3+4 0.67 penultimate 
— — ■ — — H. schineri (Giraud) 
Synopsis. Frons broad, twice width of eye, narrowly 
projecting above eye in profile; 2 ors, 2 or 3 ori; 
gena angular, deepest in center below eye, 0.20- 
0.25 eye height; mesonotum grayish black, weakly 
shining, with 2 strong dc but not infrequently a 
3d of varying length also present; wing length 
from 2 mm in male to 3.1 mm in female; squama dark 
gray, fringe black; male genitalia with aedeagus as 
in figures 155, 156. 
Host/Early Stages. Populus fremontii , P. tremu - 
loides , JP. trichocarpa , probably other Populus spp. 
Larva forming oval gall (fig. 157) in current year's 
growth of young twigs, pupating in gall, emerging 
in spring or early summer; puparium grayish brown. 
36 
