1 GO IIY.MEXOPTEllA OF AMERICA. [PABT I. 



the same species, as it happens to be more or less developed); 

 and at the summit two other teeth separated at the post-scutel 

 by a sort of groove or wide Bssure The concavity is in general 

 punctured, but is often striate in the middle or toward the base. 



The Ancistrocerus of this division are very common, both in 

 Europe and North America; one can even find corresponding 

 types among the species analogous to the two countries. How- 

 ever, I have never met the same identical species upon the two 

 continents. 



Here, as in other solitary wasps, the American species are 

 generally less ornamented with yellow than the European ; the 

 bands are narrower and the wings have a much greater tendency 

 to pass into brown-violet. In short, the American types have a 

 more sober appearance. 



A. Form lengthened, slender. 



8. A. tigris Sauss. — Sat ruiuutus, niger, puuetatus, gracillimus; meta- 

 Doti foveola subrugosa, acute marginata, utrinque in dentem exenrrente, 

 marginibus rectis ; puncto in basi mandibularum, J maculis 4 in cbypeo, 

 puueto frontali et post-oculari, liuea in scapo, fascia bilobata pionoti^ 

 macula subalari, 2 scutelli, post-scutello et abdominis seirmentoruui 

 marginibus anguste, tibiis tarsisque, flavis ; antennis sublux ferrugi- 

 neis ; alis byaliuis, apice fusco nebulosis. 



?Odyn. dcedaleus Harris Cat., 1833, p. 589. undescribed. 



Odyn. tigri* Sauss. Revue Zuol.. IX, 1S57, 273. 



fOdgn. pertinax 1 Sauss. Et. Vespides, III. 1851, 216, 108, % . 



OJyn. cervus Sauss. Rev. Zool., X, 1S58, 105. & 



9. Total lengtb, 11 mm.; wing, 8 mm. 



£ . Total lengtb, 8 mm. ; wing, 6 mm. 



9. Small. Form very slender, much lengthened, but de- 

 pressed, not cylindrical. Clypeus pyriform ; coarsely punc- 

 tured, terminated by a little border, hardly concave, but appear- 

 ing at times as if bidentate, because of a black and shining 

 depression. Thorax much lengthened, prothorax scarcely re- 

 tracted before, edge delicately upturned; its angles not spinose. 

 Anterior portion of mesothorax often presenting a little smooth 

 line and the posterior part two grooves. Scutel flat Post- 

 scutel arcuate on its posterior border. Metathorax having its 

 hinder plate clearly marked, its surface dull subrugose, formed of 

 two plane inclosures of a pentagonal shape, very angulate, 



1 Small male, not easy to determine. 



