332 HYMENOPTERA OF AMERICA. [PART I. 



the posterior border. The border of 2d and following segments 

 oilers a very much weaker punctuation. The head and thorax 

 are densely, but quite finely punctured. The abdomen does not 

 offer any swelling at the base of i2 < i segment beneath. 



Black; a dot on the mandibles, a frontal and post-ocular dot, 

 scape beneath, anterior margin of prothorax, a spot under the 

 wing; two dots on teguke, post-scutel, a line on each side of 

 metathorax below, and the margin of segments 1, 2, luteous ; 

 tibiae with a yellow line ; femora 1, 2, spotted with yellow at 

 the apex. Wings dusky, margined with gray. 



Uab. Guadaloupe. Collection of the Marquis of Spinola. 



2. Form less cylindrical, not much elongated, the thorax more 

 crowded together, often short and wide anteriorly, con- 

 tracted posteriorly. Metathorax more convex, rounded; 

 its fossette generally small, but always distinct. Abdomen 

 ovoid or irregular, the first segment narrower than Ike 

 second, having no longer the shape of an elongate-bell, 

 widened anteriorly, which receives the second segment, but 

 is not truncate anteriorly, not having an anterior and a 

 superior face, but the two faces lost in a continued curva- 

 ture ; this segment not as sessile; second segment more 

 swelled than in the preceding, short and convex, contracted 

 at base to fit into the first 



Insects in general strongly punctured ; often velutinous. 



(Group of 0. Huastecus, otomitus, etc.) 



The type of this group is not easily defined, because each 

 species unites only a part of the characters above indicated, the 

 group being composed of an agglomeration of very divergent 

 species. Among the Stenancistrocerus this type is reproduced 

 by a A. Sumichrasli, Guzmani, etc. 



All the species are of small size; they seem to be very numerous 

 in the southern part of the northern continent. 



It becomes more difficult to distinguish the numerous little 

 wasps, because the species are quite approximate to each other, 

 and the character of their punctures and forms varies between 

 certain limits, so that one can only feel sure about them, bv 



