412 NEW YORK STATE MUSEUM 
c Abdomen dark red, the segments margined with fuscous, length 
I mm; 5th antennal segment having the stems with a length 24 
and 4 times that of the diameters, respectively, trinodose 
(Cecidomyia) subtruncata Felt} (€ so 
cc Abdomen fuscous brown, length 1 mm; 5th antennal segment having 
the stems with a length 1% and 3 times that of the diameters, 
respectively Hf 5 eee bay eae cele atone eat MOTE INE) 1h Sor, Cy OB 
aaaa Ventral plate long, emarginate 
b Ventral plate tapering distally, roundly emarginate 
c Dorsal plate short, roundly emarginate, the 5th antennal segment 
having the stems with a length 114 and 2% times that of the 
diameters; bred sfrom) jo0o0tss Ol Grant luenyacueonitoeais ie ieee 
Cait tiltery aves ns isps ©5070 
cc Dorsal plate short, narrowly and triangularly emarginate, the 
lobes produced laterally; abdomen yellowish, length 1 mm; 5th 
antennal segment having the stems with a length 2% and 3% 
INES. We OH Wie GHAMMEHATS., cose coc PUDIGGUc a mM, So; C. O86 
bb Ventral plate long, slender, broadly emarginate 
c Dorsal plate triangularly emarginate, the lobes truncate 
d Abdomen reddish brown, length .75 mm; 5th antennal segment 
having the stems with a length 3 and 4 times that of the 
abe Noein see ne eRe nels Oiainrm nig io ob aakro SxMECMSA Wy Gd Co 220 
bbb Ventral plate long, broad, scarcely tapering, very broadly emarginate © 
c Dorsal plate short, triangularly emarginate, the lobes truncate 
d Abdomen a fuscous reddish brown, length 1.5 mm; 5th antennal 
segment having the stems equal, each with a length 3% times 
its" diameters. sckiren state ere ee DrAEGNSiS im, Sd, Co Wai 
dd Abdomen reddish brown, length 1.25 mm; 5th antennal segment 
having the stems with a length 1% and 2% times that of the 
GCWENTMEWEIS 5 660000806 (Geile 1d omitysiia))sacate panties Melia Gacy 
cEcIpomyIA Meig. 
This, the oldest genus of the group, originally included all forms 
referable to this family. It is at present restricted to a large number 
of Diplosids having simple claws, the third vein uniting with costa 
beyond the apex and not presenting characters given for the pre- 
ceding genera. The members of this group appear to live largely in 
leafy tissues, though one form, Cecidomyia resinicola 
O. S., occurs in exuded pitch masses. This genus includes the wheat 
midge, Ceci diomy ia, tr tricone Kanby es ancpecicsionesprimlercce, 
nomic importance. 
Key to species 
a Ventral plate long 
b Ventral plate broadly and roundly emarginate, the lobes diverging 
strongly 
c Fifth antennal segment having the basal portion of the stem with a 
length less than its diameter, the circumfili indistinct or wanting 
