ODYNERUS. 195 



2. Form very slender. Metathorax not so distinctly produced 

 behind the x>ost-scutel ; its concavity large, limits rather 

 well defined. First abdominal segment elongate, bell-shaped, 

 ■ having a distinct suture. 



(Group of 0. histrio.) 



A. 'First segment of the abdomen rather funnel-shaped or bell- 

 shaped, truncate anteriorly. 



32. A. Fariasi Sauss. — Sat minutus, gracilis, foratninato-punctatus ; 

 pronoto bidentato, metathoracis foveola grosse punctata, angulata ; ab- 

 dominis primo segmento infundibuliformi, basi truncato, secundo 

 augustiore ; antennis et tarsis subtus ferrugineis ; pronoti margiuibus 

 tenuissirue albido-liuibatis, post-scutelli limbo autico, macula subalari, 

 lineolis 2 in metanoti cantbis abdoininisque vittis 2, albidis. — % . Cly- 

 peo albido, elougato, bidentato. 



Odynerus Farias Sauss. Rev. de Zool., 1857, IX, 274. 



9 % . Total length, 11 mm. ; wing, 8 mm. 



9. Slender, lengthened. Head densely cribrose with great 

 punctures. Clypeus bearing some great shallow punctures, 

 strongly bicarinate toward the bottom. An impressed point on 

 the vertex. Thorax smooth, cribrose, with holes slightly sepa- 

 rated ; metathorax rugose above. Prothorax scarcely retracted 

 before; its anterior border concave; its angles spiniform. 

 Metathorax retracted and slightly prolonged behind the post- 

 scutel, then truncate ; its posterior plate forming rather a 

 truncation than a concavity ; this plate a little triangular ; 

 widened at the summit, retracted below, its form sharply defined, 

 although with little or no border ; having its latero-inferior 

 borders armed with a trenchant edge directed backward, and which 

 terminates inferiorlyin two strong teeth between which fits the 

 base of the abdomen; the contour of the cavity angulate, forming 

 on each side a sharp angle, but which is not detached in the form 

 of a tooth ; the summit of the plate cribrose with great punc- 

 tures, -but the lower portion is excavated into a striate furrow, 

 punctured, and divided by a vertical carina. The whole plate 

 defined in a manner comparable to a double pentagon, character- 

 istic of the Ancistrocerns, properly called (comp. p. 157, ex. O. 

 capra), but here the pentagon is lengthened, higher than wide. 

 Abdomen lengthened, the first segment prolonged, bell-shaped, 



