ODYNERUS. 237 



/ations and hooks a little rufous. Wings subhyaline or smoky; 

 the anterior margin rather ferruginous. 



Var. a. A little yellow mark on the forehead. 



b. A little yellow line in the middle of the margin of the 1st 

 segment. 



c. The post-scutellar metathoracic eminences indistinct or not 

 developed. 



?. Clypeus convex, strigate, bicarinate, terminated by two 

 angles or teeth, sometimes ferruginous. 



% Clypeus rounded, polygonal, pale yellow, widely truncate, 

 its inferior angles almost toothed. A line on the mandibles and 

 on the scape of the antennae, a spot between the antenme, inner 

 orbits, a line on the anterior side of the tibiae, pale yellow or 

 ferruginous. Antennae without a terminal hook. 



Var. a. Only the 2d, 3d, and 4th abd. segments margined with 

 yellow. 



Bess. a. cliff'. — This insect has the appearance of 0. diabolicus, 

 but it is a little larger and is easily distinguished from it by its 

 metathorax, destitute of lateral angles, but having elevated ridges 

 separated by fissures from the post-scutel. The clypeus % is more 

 truncate ; its inferior margin being wide. — It differs also from 0. 

 brachygaster, by its metathorax without angles, and by its deep 

 black, not grayish color — velutinous as in 0. nasidens and its 

 allies. 



Hab. The Argentine Republic. Buenos Ayres. 1 9, 5 %>. 



B. All the abdominal segments margined with yelloio or rufous. 



a. Superior edges of metathorax not sharp. 



?©. O. Periiemsis Sauss. — Niger, cinereo-sericeus ; thorace antice 

 latiore quaui postice; metathorace excavato, strigato, inferis tantum 

 canthis arntis ; abdomine conico, basi lato, truncato, 2' 1 segmenti margine 

 crasse punctato ; post-scutelli et metanoti punctis 2 minutis, abdouiinis- 

 que segmentorum limbo late, pallido-flavis ; 2' 1 fascia utrinque aucta ; 

 feuioribns tibiisque obscure rufis ; alis subhyalinis, costa subferruginea. 

 Longit, 11-12 mm. 



$>. Clypeo rotuiidato, emarginato, valde punctato, dentibus 2 distantibus 

 termin:ito. — % . Clypeo truncato. 



Odyn. Peruensis Sauss. Et. Vespid. Ill, 253, 129, pi. xii, fig. 4, J (1854). 

 Hab. Peru. (Typus in Mus. Tarisiensi.) 



