NORTH AMERICAN HYMENOPTERA. 317 



the posterior face with larger fossiilets, Imt they are not so well defined ; the 

 nietapleuraR with some coarse folds. AMonicn as in tugrifiis, except that the 

 p.Vfjidiuni is longer and is coarsely punctured throughout ; black, shining; man- 

 dibles, except apical portion, teguljE, tubercles, apex of femora, fore tibiw in 

 front, the remaining tibiae at base and apex, and the tarsi more or less, yellowish. 

 Length 6 mm. 



Fort Collins, Col. (C. P. Gillette), one specimen. The abdomen 

 in this sjiecies is n)ore distinctly petiolate than in any of the others. 



6. I>iofIontn$$ iiigritiii« n. sp. 



9- — Eiuargiuatiou of labrum strong, the teeth formed by it obtuse; front 

 shining, with strong separated punctures, the medial impressed line faint; the 

 cheeks and vertex more sparsely punctured than the front; ocelli situated in 

 slight pits, especially the anterior one ; dorsulum punctured like front, the punc- 

 tures dense before the scutellum ; scutellum punctured likewise, with a strong, 

 medial impression ; mesopleurae and metapleurse with strong, oblique rugse, the 

 metathorax above and behind with strong, irregular, broad fossulets, which are 

 larger on posterior face. Wings hyaline, iridescent, nervures and stigma black ; 

 tibife armed with bristle-like, testaceous spines. Abdomen shining, with ex- 

 ceedingly fine and close punctures, beneath the punctures are larger and more 

 sparse; pygidium on basal half with large, sparse punctures; black, shining; 

 clypeus, mandibles and legs, sparsely clothed with pale hairs; tegulfe and tibial 

 spurs testaceous. Length 5—6.5 mm. 



Colorado. Five specimens bearing the mss. name nigritus Cress. 

 The general appearance of this si:»ecies and Gillettei is like Passa- 

 Iceeus, 



AMMOPLAXUS Giraud. 



Aiiiiiioplaiius? coliiinbianiiN Kohl. 



" Length 3 mm. Black, the mandibles, the anterior tihije. a basal ring on the 

 middle and posterior tibise and the tarsi yellow ; the posterior tarsi brownish, J . 



" Clypeus with a raised middle part, which has at its base a pointed protuber- 

 ance, below this the middle part is lightly impressed. Die Fiihler sind nicht so 

 sehr weit unten wie bei Cel'ta troglodytes oder Ammophmiis Perrisii am Kopfschilde 

 selbst eingelenkt, so das die Einleiikungsbeulen nicht nebeu dem hockerigen 

 Mitteltheile, sondern oberhalb des Kopfschildes, auf der Stirne zu stehen koin- 

 men. Frontal line distinct. The triangle formed by the position of the ocelli, 

 has a decidedly less height than in Celia troglodytes, in which it is almost equi- 

 lateral. Collar deep under the level of the dorsulum (this is of an entirely dif- 

 ferent form than in Celia troglodytes, having a straight line in front, with obtuse 

 side angles) ; the mesopleuric show the longitudinal furrow going above from the 

 episternal suture. Metathorax above quite netted, on the sides irregularly 

 wrinkled. Dorsulum unusually finely wrinkled, nearly smooth; pleurre more 

 shining. On the upper half of the cubital transverse vein there is a stump of a 

 vein, so that it seems to me as if a second cubital cell had disappeared through 

 the partial combination of the second cubital transverse vein with the first, and 

 by the obliteration of the part of the cubital vein which closes the second cubital 

 cell behind." 



British Columbia. 



TEANS. AM. ENT. SOC. XIX. DECEMBER, 1892. 



