72 
One female, Dyar's type. Mr. H. G. Dyar characterizes the last 
larval stages from solitary larva? found on the edges of the leaves of 
white birch at Keene Valley, N. Y. 
43. Pteronus unicolor new species. 
Female. — Length 6 mm.; moderately robust, shining; clypeus broadly 
and shallowly emarginate, lobes small, rather pointed; ocellar basin 
distinctly denned; frontal crest narrow, unbroken; antennal fovea 
broad, rounded, subtriangular, deeply excavated; venation normal; 
stigma elongate, acuminate; sheath tapering on lower margin to rather 
pointed apex, superior margin straight or but slightly convex; claws 
deeply notched, rays equal. Color uniformly yellowish ferruginous, 
the latter color most noticeable on vertex, dorsum of thorax and abdomen 
and the tips of hind femora, all the tibiae and tarsi; veins brown, except 
extreme base of stigma, which is white; costa somewhat paler than 
other veins, especially at base. 
One female. California. (Coll. Am. Ent. Soc.) 
44. Pteronus longicornis new species. 
Male. — Length G to 7 mm.; not very robust, shining; clypeus shal- 
lowly and broadly emarginate; sides of ocellar basin and frontal area 
rounded, indistinct; antennal fovea shallow, indistinct; antenna? very 
long, slightly tapering, nearly as long as body, joints nodose at tips, lower 
ones flattened, joints 3 to 5 subequal; procidentia very broad, one-third 
as wide as last segment, rounded at tip, strongly constricted basally; 
claws deeply notched, rays subequal; intercostal vein nearly at right 
angles to costa and its own length anterior to basal vein ; third cubital 
cell nearly twice as wide at apex as at base and three to four times as 
long as wide at base; venation otherwise normal; stigma rather broad, 
ovate, rounded beneath, with slight angle near center. Color black; 
clypeus, mouth parts, angles of pronotum, teguhe, narrow lateral mar- 
gin of abdomen with posterior margin of the central segments and the 
two terminal segments, venter of abdomen, and legs yellowish ferru- 
ginous; tips of the posterior tibia' and their tarsi, black; veins, includ- 
ing stigma and costa, the latter nearly to base, dark brown. 
Many specimens. Michigan, New York, and Long Island (Coll. U. S. 
Nat. Mus.), and Massachusetts and Canada (Coll. Am. Ent. Soc.) 
45. Pteronus iridescens Cresson. 
1880. Nematus iridescens Cresson. Trans. Am. Ent. Soc, vm, p. 5. 
Male. — Length 5 to 6 mm.; not very robust, shining; clypeus circu- 
larly and rather deeply emarginate; ocellar basin large, lateral walls 
and frontal crest distinctly defined, the latter unbroken; antennal 
fovea very shallow, indistinct, elongate; antennae robust, flattened, 
short, not much longer than head and thorax, tapering, joints 3 and 4 
