ODYNERUS. 241 



flavis ; abdominis seginentoruin l 1 , 2 1 roargine flavo, 3\ 4- tenuiter 

 flavesceute ; tibiis l ,s , 2 la linea ilava ; alia ferrugineis macula radiali 

 fuse a. 



Odijn. LaPlatce Sauss. Rev. et Mag. de Zool. XXII, 1870, 52, 2 J . 

 9. Total length, 12 mm. ; wing, 9.5 mm. 



?. Form rather slender, very much as in 0. cubensis and 

 tibialis. Clypeus pyriform, strigate-punctate, terminated by two 

 little ferruginous teeth. Head and thorax densely punetate. 

 Post-seutel truncate, ridged but not crenulatc. Metathorax 

 excavated in its whole width, forming on each side an indistinct 

 angle ; its superior edges convex, very sharp, their superior 

 extremity hardly separated from the post-scutel by a fissure, not 

 forming salient teeth; the inferior edges straight or a little arched 

 concave. Abdomen polished, silky, the first segment as wide as 

 the 2d, almost sharply truncate. 



Black; scape ferruginous beneath; a fine line along the poste- 

 rior edge of prothorax and a very slender one along the anterior 

 margin, on each side, two spots on the tegulse, a mark under the 

 wing, a line on post-scutel, and the superior edges of metathorax, 

 yellow. Segments 1, 2 of the abdomen narrowly margined with 

 yellow ; the extreme margin of the 1st brown ; segments 3-5 

 narrowly margined with brown or yellowish. Knees and claws 

 ferruginous. Tibiae 1st and 2d anteriorly with an indistinct yellow 

 line. Wings ferruginous along the anterior margin ; the radial 

 cell brown. 



Bess. a. diff. — This is possibly the same as 0. prsecox, and I 

 should not have distinguished this from it, if in the description of 

 praecox it was not said that the metathorax was rounded, while 

 here the superior edges are very sharp. — It much resembles 

 tibialis, but the livery is rather different and it varies also in its 

 metathorax not sharply bidentate, its abdomen not as conical, its 

 first segment nof as sharply truncate, shorter, etc. — From zonaius 

 it differs in its livery and the same changes in the form of the 

 prothorax. 



Hab. The Argentine Republic. Buenos Ayres. 



W. O. tibia Bis Sauss.— Niger, oinereo-hirtus ; dense panotatua ; thorace 

 quadrate-, 9 lorigiore quam latiore, $ oubioo, depresso ; metanoto bi- 

 dentato, aoutissime margiuato; abdomine valde oonioo basi aoute trun- 

 oatb et oa nth urn aoutum transversum effloiente; segmentorara 2 5 

 margin© punctato. Macula mandibnlaram, pronoti margin©, tegulis, 

 '6 



