NORTH AMERICAN HYMENOPTKRA. 237 



9. — Apex of femora, tibia; and tarsi, yt'llow-fcrnigiiious; hind tarsi very feebly 



spinose crassiis. 



Legs, except apex of tarsi, black ; bind tarsi ratlier strongly si)inose. 



pepticus. 



10. — Abdomen in ])art red 11. 



Abdomen entirely blaek f ulviv<Mif ris var. 



11. — Two apical joints of the antennse narrow and elongate, nuicli narrower than 



.joints 9 — 11, which are visibly broadened l'iilviveiilrJ!i$. 



Two apical joints of the auteuuge somewhat spatulate, broader than the 

 two preceding joints spatulatu!<«. 



1. Tachytes validiis Cress. PI. XI, figs. 1 and 2, 



9- — Anterior margin of the dypeus with a broad, quadrate production me- 

 dially and armed with three small teeth on each side, the two outer being most 

 distinct, the production with an impression, which gives it the appearance of 

 being bituberculate; space between the eyes at top about equal to the length of 

 the second and third joints of the antennse united ; first joint of the flagellum 

 about one-quarter longer than the second ; vertex with rather strong, separated 

 punctures, parted by a distinct sulcus, which originates from a strong depression 

 just behind the ocelli : dorsulum very finely punctured ; scutellum punctured 

 like the dorsulum, strongly convex, scarcely impressed in the middle; meta- 

 notum with an exceedingly slight, impressed line down the middle, which is 

 broadened into a dimple-like fovea at apex, being again narrowed into a deep 

 sulcus on the posterior face; tibiae armed with short, strong spines, which are 

 shorter than those on fore tarsi; abdomen with exceedingly fine punctures, 

 almost smooth ; beneath shining, with large, sparse punctures; pygidium convex, 

 depressed along the sides on the apical portion, black ; basal half of mandibles, 

 scape beneath, tegulge, legs except the coxfe, trochanters and greater part of 

 femora, yellow-ferrugitious ; face and clypeus densely covered with bright, sil- 

 very pile and with long, sparse, golden hairs. Thorax and femora densely clothed 

 with dark golden pubescence, becoming sparse on the pectus. Wings hyaline, 

 the nervures ferruginous, marginal cell hardly extending out as far as the apex 

 of the third submarginal, second submarginal cell broader than the third at the 

 top; dorsal segments 1 — 4 of the abdomen with a broad, apical, silvery band ; 

 first segment above clothed with grayish hairs: ventral segments 2 — 5 each with 

 a transverse row of stiff hairs before their apex, the fifth dorsal segment with a 

 similar row; pygidium clothed with silvery pile. Length 18—22 mm. 



%. — Differs from the female as follows: anterior margin of clypeus not so 

 strongly produced in the middle, the process more strongly impressed : the sulcus 

 which divides the vertex is shorter; depression behind the ocelli not so strong; 

 joints 1 — 5 of the flagellum strongly rounded out beneath, especially joints 2 — 4 : 

 scutellum distinctly impressed medially; metathorax furrowed as in the female : 

 the thorax is generally less densely clothed with pubescence; apical margins of 

 ventral abdominal segments testaceous; eiglith ventral plate bifurcate ; second 

 and third submarginal cells at the top about C(iual. Length 15—19 mm. 



Texa,s. 



2. Tachytes inaiKlibiilaris Patt. 



9 .—Clypeus as in validtis, but the median process is narrower, the outer lateral 

 tooth is distinctly separated from the inner ones, and is more obvious; space 



TK.\NS. AM. KNT. SOC. XIX. AUGUST, 1892. 



