ODYNERUS. 245 



A very distinct species in the form of its mctathorax. The 

 lateral tooth of metathorax is formed principally by the lateral 

 ridge, and placed quite outside of the margin of the excavation, 

 which is situated more inside, and rather distant from the tooth. 

 There is, in addition, a very long spine on each side, on the 

 inferior edges near the articulation of the abdomen. It has much 

 the appearance of 0. argentinus, but the metathorax is without 

 lateral angles. 



Hab. South America; Brazil, Venezuela (author's collect.). 



b. Abdomen varied with black and rufous. 



81. O. Eriiinys Lepel. — Niger, valde punctatus, gracilis; thorace 

 postice attenualo ; metanoto longe bispinoso, canthis acutissimis mar- 

 ginato; abdomine basi truncato ; in marginibus valde punctato ; ore, 

 macula frontali et autennarum articulis 1-5 rufis; prouoto, tegulis, 

 post-scutello, metanoti angulis, abdominis primo segmento superne et 

 secundi margine pedibusque, rufis ; alis infuscatis, costa subferruginea. 



9« Clypeo piril'ormi, crasse punctato, bicarinato, apice biangulato, apice 

 et basi, rufis. 



%. Clypeo polygonali, luteo, argenteo-sericeo, subbidentato ; anteuuia 

 apice baud uncinatis. 



Variat. Prirno et secuudo abd. segmentis flavo'-marginatis. 



Odjn. Erynnis Lep. St. Faegeau, Hymen. II, 645, 30 $ (1841).— Sacss. 

 Vespides, I, 178, 70. 



Total length, 16 mm. ; wing, 11 mm. 



9. Form slender, moderately lengthened. Head and thorax 

 coarsely cribrose ; this last quite lengthened, retracted behind ; 

 post-scutel finely crenulate; metathorax having its posterior face 

 a little retracted ; strongly excavated, a little oblique, smooth, 

 finely striate; bordered with abrupt very trenchant ridges, which 

 are armed on each side with a long spiniform tooth, prism-shaped, 

 and prolonged obliquely backward ; it is placed sufficiently low 

 for the inferior ridges of the metathorax to be almost horizontal ; 

 these last offer beyond on each side of the valves o( articulation 

 with the abdomen, a second distinct spine. The superior ridges 

 are sinuous and terminate under the post-scutel by an arc or 

 nearly a right angle; seen in profile their summit terminates in a 

 pyramidal, although but little acute, angle, placed quite behind 

 the post-scutel and separated from it by a triangular notch. 



