52 
Mus.) vary from above in having an elongate upper middle cell in hind 
wings, which, however, does not exceed lower, and in that the inter- 
costal is a little anterior to basal. 
Food-plants: Populus and Salix. 
8. Pteronus marlattii Dyar. 
1894. Nematus marlattii Dyar. Trans. Am. Ent. Soc., xxi, p. 305. 
Female.—Length5.5 mm.; moderately robust, shining; clypeus broadly 
and shallowly notched; ocellar basin deep and with well-defined walls; 
frontal crest unbroken; antennal fovea large, triangular, deeply exca- 
vated; antenne slender, third and fourth joints subequal; venation 
normal; stigma broad, ovate, widest at center, rounded on lower margin; 
sheath broad, obtusely pointed, upper margin slightly emarginate; 
claws deeply cleft, rays subequal. Color of head, thorax, epimera and 
dorsum of abdomen for the most part, and outer half of posterior 
femora black; apices of posterior tibize and their tarsi dusky; face 
below antennie, mouth parts, orbits, angles of pronotum narrowly, 
tegule, narrow apical margin of dorsal segments and last two segments, 
venter except epimera and some dusky spots on lateral margin of 
abdomen, and legs except as noted pallid, inclined to yellowish; apex 
of sheath brownish; antennwe ferruginous beneath and toward apex; 
veins, including stigma and costa, the latter nearly to base, brown. 
Characterized in manuscript by me from a specimen collected in New 
Hampshire (Coll. Am. Ent. Soc.); first published by Dyar from a 
specimen bred from larva on alder (Dyar’s Coll.). 
9. Pteronus atriceps new species. 
Female.—Length 6.5 mm.; moderately robust; clypeus very broadly 
and shallowly emarginate, lobes minute; frontal crest strongly devel- 
oped, entire; lateral walls of ocellar basin not strongly raised; fovea 
elongate, deep; antenne medium, with joints 3 and 4 subequal; third 
cubital cell not more than one-third as wide at base as at apex, about 
four times as long as wide at base; venation otherwise normal; stigma 
broad, rounded on lower margin, tapering gradually from near base to 
tip; sheath broad basally, tapering to an obtuse tip, upper margin 
straight; claws not very deeply notched, inner ray nearly as long as 
outer. Color black, shining; tips of clypeus, mouth parts, tegulie, 
legs except cox, and venter of abdomen, including lateral edges of 
dorsal sclerites, yellow; upper posterior orbits and outer angles of pro- 
notum reddish; legs slightly infuscated, particularly the tarsi; sheath 
dark brown; veins brown, stigma unicolorous, brown. 
One female. Nevada. (Coll. Am. Ent. Soc.) 
10. Pteronus coloradensis new species. 
Female.—Length 6 mm.; rather elongate, surface shining; clypeus 
deeply, circularly emarginate, lobes rounded; frontal crest and sides of 
