7 • Radial cell open... 8 
Radial cell closed.. 
8. Scutellum conical, tapering to a blunt point, foveae open behind. 
Mesoscutum polished, parapsidal grooves percurrent. mesopleuron striate# 
Gall on Potentilla.GONASPIS Ashmead 
Otherwise .. 9 
9# Wing not pubescent, not ciliate, areolet absent. 
Galls on Lygodesmia, Silphium.. ANTISTROPHUS Walsh 
Wing pubescent and ciliate ( cilia short in Liposthenes).. • 10 
10. Mesoscutum smooth and polished# Face striate# Gall on Potentilla# 
DIASTROPHUS Hartig 
Mesoscutum dull and sculptured. 11 
11# Mesoscutum bare and beautifully coriaceous. Areolet wanting. Mesopleuron 
striate# Gall on Glechoma...LIPOSTHENES Foerster 
Mesoscutum dull with setigerous punctures, the hairs appressed. Areolet 
present. Galls on various harbaceous plants.. AYLAX Hartig 
12# Segment 5 of antenna not distinctly longer than 4. Mesoscutum dull. 
Galls on Composites: Lactuca, Prenanthes.AUIACIDEA Ashmead 
Segment 5 of antenna longer than 4. Mesoscutum shining, coriaceous under 
magnification of X 65. Gall on Tsraxacum.GILLETTEA Ashmead 
1^. Hypopygium plow-share-shaped (Fig.18). Galls on rose. • . DIPLOLEPIS Fourcroy 
(- Rhodite3 of authors) 
Hypopygium not plow-share-shaped. 14 
14. Mesoscutum emarginate behind and joined to scutellum without a suture, black, 
smooth, and with at most but traces of parapsidal grooves; wings ample, 
radial cell elongated# Body wall thin. Galls on white oaks only. There 
is an alternation of generations in this genus. Six subgenera have been 
proposed. NEUROTERUS Hartig 
Mesoscutum and scutellum distinctly separated by a suture so that the scutellum 
scutellum has a distinctly-margined, nearly straight or arcuate front 
edge in all winged forms.... 15 
15. Tarsal claws with a tooth (Fig. 25 ) • .. 1 6 
Tarsal claws simple (Fig. 25). 29 
Here is is usually necessary to remove a last tarsal segment, 
mount on a slide in a drop of water, crush under a cover glass 
and examine under high power to be sure of this point as the tooth 
is Often obscured by dirt or is but weakly developed# 
16• Wingless or with reduced wings reaching little beyond tip of abdomen. . . 17 
Fully winged. ...... . ..... 21 
17# Ventral spine slender, needle-like, bare except for slight pubescence on 
under side, several times as long as broad in side view.. 18 
Ventral spine bristly, the hairs diverging and reaching beyond the tip, of 
various forms but not needle-like. 19 
18# Antennae 15-segmented# Parapsidal grooves absent or incomplete. 
From galls on leaves of white oaks in fall. . • • • PHYLLOTERAS Ashmead 
Antennae l4-segmented# Scutellum with a transverse groove at base, the 
disk almost circular. From small galls in numbers on leaves of 
white oaks in fall. XYSTOTERAS Ashmead 
19. Ventral spine tapering gradually to a point Fig.24,a,b.)• Antennae stout, 
14-s eg mented. Malar groove present. Abdomen longer than head plus 
thorax. Tergite II not foliiform.agamic XANTHOTERAS Ashmead 
Ventral spine broad distally (Fig. 24, e to h)••••••••••••#• 20 
14 
