1G2 THE CANADIAN ENTOMOLOGIST 
dorsal face set with abundant spicules, the extreme apex a c>-lin- 
drical spine; this appendage is bent slightly dorsad at its tip; 
ventral appendage much longer and more slender from enlarged, 
brown bases, with about six scattered teeth, at the apex bent 
strongly ventrad. 
Habitat. — Colorado. 
Holotype. — cT, Platte Canyon. Colorado, altitude 10,000 feet, 
August 26. 1915, (Oslar). 
Closest to M. paulus Bergroth (Alaska) but the hypopygial 
details different, the dorsal appendage of paulus being shaped as 
follows: short, bent slightly inward, the apex an acute point, the 
surface of the appendage indistinctly denticulate; teeth on the 
rentral appendage differently arranged. 
Molophilus ursus, new species. 
Antennae of the male not elongated; general coloration dark 
brown, the pronotal scutellum and the humeral angles yellowish; 
male hypopygium short with the ventral hooks powerful, at about 
mid-length enlarged and densely set with sharp, appressed spines. 
Male. — Length 3.5 mm.; wing 5 mm. 
Female. — Length 4.5 mm.; wing 5.8 mm. 
Rostrum and palpi dark brown. Antenna- short, dark brown, 
the flagellar segments oval-cylindrical with long, dark verticils. 
Head brownish gray with long bristles. 
Pronotum light yellowish. Mesonotum dark brown, sparsely 
gray pruinose; a conspicuous light yellowish triangle occupying 
the humeral portions of the pra-scutum before the fovea?. Pleura 
dark brown. Halteres dark brown, the bases pale, the knobs 
with pale, silky hairs. Legs with the coxae and trochanters yel- 
lowish; femora brown, pale at the extreme base; tibiae and tarsi 
dark brown. Wings dark-coloured; veins dark brown with long, 
dark brown hairs. Venation : Cu\ — Ms moderate in length, a 
little shorter than the basal section of M^■^■2; in one paratype 
very much shorter, subcqual to the basal deflection of Cm. 
Abdomen dark brown, the segments ringed caudally with 
paler; hypopygium short, stout, dark coloured; ventral hooks 
short and powerful (Fig. 7, 6), narrow basally, gradually enlarged 
to about midlength, the ojiter angle thence produced QUtward as a 
strong, black, slighth' curved tip. the middle portion of the ap- 
