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 metathoraeic 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 antenna3, a spot between the antennae, 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. 

 br achy g aster, by its metathorax without angles, and by its deep 

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

 allies. 



Hob. The Argentine Republic. Buenos Ayres. 7 9, 5 £. 



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



a. Superior edges of metathorax not sharp. 



^O. O. IPei'iaemsis Sauss.— Niger, cinereo-sericeus ; thorace autu-e 

 latiore quain postice; metathorace exoavato, strigato, inferia tantum 

 canthis acutis ; abdomine conico, basi lato, truncate), 2' segment] margine 

 crasse punctate; post-scutelli et metanoti pnnotis 2 minutis, abdominis- 

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

 femoribus tibiisque obscure rufls; alis subhyalinis, oosta subferrugiuea. 

 Longit, 11-12 mm. 



9« Clypeo rotundato, emarginato, valuY pauotato, dentibus 2 distantibua 

 terminate — % . Clypeo trunoato. 



Odyn. Per'uensis Sauss. Et. Vespid. HI, 253, L29, pi. xii, fig. 4. V (1864). 

 llab. Peru. (Typus in Mus. Parisiensi.) 



