24 THE CANADIAN ENTOMOLOGIST 
Holotype, cf, Platte Canyon, Colorado; July 17, 1915 (Oslar). 
Allotype, 9 , with the type. 
Paratopotype, 9 . 
Differs from A. saxicola O. S. of Eastern North America in 
the antennal flagellar segments less elongated and paler coloured; 
liead more yellowish, the thorax without stripes, etc. 
Tribe Eriopterini. 
Genus Ormosia Rondani. 
Ormosia nimbipennis, sp. n. 
Coloration reddish brown; wings dusky gray; cell 1st M2 of 
the wings open, the outer deflection of Mz lacking; anal veins 
convergent. 
Male.- — Length 4 mm. ; wing 5.8-6 mm. 
Female. — Length 5.4 mm.; wing 6.3 mm. 
Rostrum dull yellow; palpi brown. Antennae moderately 
elongate, uniform dark brown throughout. Head brownish gray. 
Mesonotum reddish brown without distinct stripes; interspaces 
with a dense, yellow pilosity; tuberculate pits remote from the 
anterior margin of prsescutum and closely approximated, separated 
from one another by a distance about equal to one-half the diameter 
of one; postnotum with a slight grayish pruinosity. Pleura pale 
brown with a sparse, gray pruinosity; sternum dull yellow. Halteres 
pale yellow. Legs with the coxae and trochanters dull yellow; 
femora dull yellow, only a little darkened apically; tibiae and tarsi 
dark brown. Wings dusky gray; costal region and the stigma 
brownish; veins dark brown; wing membrane with abundant, 
short, appressed, black hairs. Venation: cell 1st Mi open, the 
outer deflection of Mz being absent; cross-vein r usually a little 
shorter than the portion of J?2 before it; i?2+3 about equal to the 
deflection of i?4+6; petiole of M2 short, less than the basal de- 
flection of Cu\; anal veins convergent. 
Abdomen dark brown, the hypopygium a little lighter; hypo- 
pygium with the pleural appendages acicular at their apices, black; 
a prominent median appendage, rectangular, the base and head 
slightly expanded, the latter squarely truncated or slightly concave 
across the tip. ° 
Habitat. — Northeastern United States. 
