ODYNERUS. 213 



Body hirsute with a long pile. Antenna? of males terminated 

 by a long hook or spirally curled at the. extremity. 



These are insects of Chili or the occidental side of the South 

 American Andes, adorned with sulphur-white and often with 

 rufous bands, having the wings obscure or ferruginous with the 

 extremity obscure. 



2. Pachodynerus. — Body stubbed. Thorax quadrate. Abdo- 

 men quite sessile, very conical, truncate at base. Post-scutel 

 truncate. Antennas simple in the males, not terminated by a 

 hook. 



3. Odynerus. — Form about the same as in Pachodynerus; 

 abdomen sometimes more ovate-conical, the fii'st segment being a 

 little contracted, Post-scutel generally truncate. Antenna? of 

 the males terminated by a hook. 



4. Stenodynerus. — Form slender. Abdomen cylindrical, 

 .slender, subsessile; or spindle-shaped, attenuate at base, the first 

 segment small, cup-shaped or funnel-shaped, not very sessile. 

 Post-scutel entire or truncate. Antenna? of the males terminated 

 by a hook. 



The separation of these Divisions being difficult, they will be 

 defined more fully hereafter. 



Division HYPODYNERUS. 

 (Sauss. Vespides, III, 225 ; ibid. I (2d division), p. 160.) 



Forms of insects depressed, velvety, bristling with long hair. 

 Thorax little or not at all angulate. Abdomen pedicellate or 

 sessile, with the 2d segment wide, depressed ; the first vari- 

 able but almost always formed according to the same system, 

 offering a triangular anterior face which fits itself against 

 the metathorax and a superior face, very short, divided by 

 a groove ; the meeting of these two faces forming a boss or 

 a transverse saddle-back. Sometimes, however, the first 

 segment is simply depressed bell-shajied. The abdomen is 

 not conic, but oval, depressed. 



These insects which represent the fauna of Odynerus of certain 

 regions of South America, offer an appearance very easy to define, 

 in view of the variety of their forms. . 



Above all, one can distinguish them by their velvety or long 



