210 HYMENOPTERA OF AMERICA. [PART I. 



or very small. Scape of the antennae beneath, tawny. Anterior 

 border of the post-scute], yellow ; the rest of the thorax black, 

 except a yellow dot on the appendix of the wing scale, and a 

 rudiment of an edging on each side before the wing scale along 

 the posterior border of the prothorax. All the segments of the 

 abdomen widely and regularly bordered with yellow-golden ; the 

 first bordering more narrow, feebly notched in the middle. 

 Legs black, tibiae and tarsi varied with ferruginous. Wings 

 transparent. 



Var. The posterior border of the prothorax edged with yellow. 



Bess. a. cliff. — A species very distinct by its metathorax, smooth 

 or at least more smooth than the rest of the thorax. Very near 

 to the little species of the group of 0. huastecus ; particularly 

 above all by its thorax to the 0. Peyroti, from which it hardly 

 differs but by its narrower thorax and by the feeble suture of the 

 first segment. It differs from the 0. Fariasi, by its first abdo- 

 minal segment cup-shaped, not truncate-funnel-shaped, and de- 

 prived of the crest-shaped suture ; by its metathorax less rugose 

 than the rest of the corselet, by its less slender form, etc. 

 These last characters distinguish it also from the A. occidentalis, 

 Guzmani, and the 0. fulvipes, which have a more pronounced 

 suture. 



Hab. The temperate lands of Mexico. One female from the 

 hot regions of the province of Mexico, near Cuautla (Morelos) 

 taken by my friend Mr. Sumichrast. 



Division HYPANCISTROCERUS. 

 (Hypancistrocerus Sauss. Et. Vesp., Ill, 222.) 



Head swelled. Antennae inserted low upon the fare. Superior 

 face of metathorax irroduced horizontally a little beyond the 

 post-scutel, then vertically truncate, theposteriorfa.ee having 

 a deep orbicular cavity, with very sharp margins. Suture 

 of first segment very salient. 



This type presents the extreme form of the elongate and 

 cylindrical Ancistrocerus. It forms a group corresponding to 

 Hypalastoroides, by its slender body and the peculiar shape of 

 its metathorax. 



