116 
One female. Nevada. (Coll. U.S. Nat. Mus.) A specimen from 
Ithaca, N. Y., has also been referred, doubtfully, to this species. 
Mr. H. G. Dyar reared this insect from green larvee found on white 
birch (Betula papyrifera) at Keene Valley, N. Y., and also on willow 
and yellow birch at Jefferson, N. Y. 
4, Pristiphora lata Cresson. 
1880. Nematus latus Cresson. Trans. Am. Ent. Soc., vill. p. 4. 
Female.—Length 5.5 mm.; short, very robust; head nearly as wide as 
thorax, not noticeably trilobed, finely granulate; body generally clothed 
with fine hoary pile; clypeus truncate; frontal crest and sides of ocellar 
basin entirely wanting; antennal fovea very minute, shallow, circular; 
antennie short, not longer than head and thorax, somewhat compressed, 
tapering, third and fourth joints subequal; intercostal cross nerve nearly 
interstitial with basal, inclined; third cubital cell not more than twice 
as long as wide at base; venation otherwise normal; sheath not very 
robust, tapering on both edges, with distinct scopa; cerci minute, not 
tapering; inner tooth of claw very minute. Color black; head and tho- 
‘ax Opaque, abdomen shining; ¢lypeus, apical two-thirds of first pair of 
femora and their tibix, and tarsi fulvous, inclined to fuscous; posterior 
tibive and tarsi fuscous; wings hyaline; veins dark brown; extreme angle 
of pronotum fulvous. 
Male.—Characters in general as in the female. Color the same, except 
that the female sometimes has the extreme tip of the pronotum yellow; 
antenme robust, short, strongly compressed; first cubital cross vein 
hyaline. Easily distinguished from all other males of the genus by the 
black pronotum and tegulie, and black or strongly infuscated hind 
tibix. 
Two females and one male. Nevada. (Colls. Am. Ent. Soc. and U.S. 
Nat. Mus.) 
This species is very closely ailied to labradoris, but differs particularly 
in the much wider head relative to the thorax, and also in minor details. 
5. Pristiphora siskiyouensis new species. 
Female.—Length 5 mm.; rather robust; head large, nearly as wide 
as thorax; vertex smooth, shining, with no indications of ridges; clyp- 
eus nearly truncate; antennal fovea wanting, or nearly so; antenne 
slender, slightly tapering, third joint much longer than fourth; claw 
with minute inner tooth; venation normal, except that second cubital 
is wanting. Color black, shining, including mouth parts and tegulie; 
anterior tibiv and tarsi pallid, the tarsi slightly infuscated; posterior 
tibie white, except tips, which, with posterior tarsi, are brownish, 
almost black; wings hyaline; veins and stigma brown. 
Male.—Agrees with female in colorational characters; antennze 
stouter and somewhat compressed, distinctly tapering; easily distin- 
guished by the black pronotum and tegulie from other species, except 
