68 
crest prominent, unbroken; fovea deeply excavated but not distinctly 
limited; antennie very slender, tapering, joint 4 a little longer than 3; 
venation normal, except that the intercostal vein is nearly interstitial 
with basal; sheath narrow, tapering to rounded tip; claws coarsely but 
not very deeply notched, rays subequal. Color of antenni, large spot 
including ocelli extending over vertex, mesonotum, metanotum, and 
abdomen dorsally black; orbits, face beneath frontal crest, pronotum, 
tegule, lateral area of thorax, abdomen above, venter and legs alto- 
gether yellowish or pallid; pectus brown; tips of posterior tibi, tarsi 
and extreme edge of sheath brownish; stigma and costa hyaline; veins 
otherwise brown, 
One female, reared by Mr. H. G. Dyar from a solitary larva taken 
feeding on edge of leaf of white birch. The larva was described by 
Mr. Dyar under the name of Nematus lateralis Norton. (Trans. Am. 
Ent. Soc., Xx1I, 1895, p. 307.) 
o7, Pteronus vertebratus Say. 
1836. Nematus vertebratus Say. Bost. Journ. Nat. Hist., 1, p. 218. 
1859. Nematus vertebratus Leconte, Say, Ent., 11, p. 678. 
1861. Nematus vertebratus Norton. Proc. Bost. Soc. Nat. Hist., vir, p. 158. 
1867. Nematus vertebratus Norton. Trans. Am, Ent. Soc., I, p,215. (Cat., etc., p.77.) 
1880. Nematus dorsivittatus Cresson. Trans. Am. Ent. Soc., vu, p. 10. 
1895. Nematus dorsivittatus Dyar. Trans. Am. Ent. Soc., Xx1, p. 303. 
Female.—Length 6 mm.; rather robust, shining; clypeus distinctly 
but not very broadly emarginate, lobes rounded; sides of ocellar basin 
distinctly, rather sharply raised; frontal crest rounded, broken at mid- 
dle; antennal fovea circular, shallow; antenne very long, slender, 
considerably longer than head and thorax; joints 3 to 5 subequal; vena- 
tion normal; stigma moderate, circular on lower margin; sheath rather 
pointed, lower margin regularly rounded, upper straight or slightly 
concave, bordering hairs very minute; cerci slender, scarcely tapering; 
claws not very deeply notched, rays subequal. Color light yellowish; 
antenne, spot on vertex including ocelli extending back over occiput, 
lobes of mesonotum except lateral edges, metanotum, and tergum 
centrally except apex of last sclerite black or dark brown; antennee 
lighter beneath; upper margins of hind tibize and their tarsi more or less 
infuscated; extreme tip of sheath brownish; veins brownish, including 
costa nearly to base; stigma unicolorous, pale. 
Male.—Length 4mm.; slender, shining; antenne as long as the body 
of the insect; structurally in general as the female; antennal joints 
decreasing uniformly in length from third to tip; fovea somewhat tri- 
angular, extending laterally over base of antennie; procidentia narrow, 
nearly twice as long as wide, slightly notched at tip. Color of antenne 
basally above, spot including ocelli and extending over occiput, meso- 
notum, metanotum, and dorsum of abdomen black; face below frontal 
crest, orbits, pronotum, tegulee and entire venter, yellowish; antennie 
