160 IlY.MENorTF.KA OF AMERICA. [PART 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 - >rl 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 

 continent.*. 



He e, 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. 



S. A. tigris Sauss. — Sat minutus, nisrer, puuetatus, gracillimus; meta- 

 noti foveola subrugosa, acute niarginata, utrinque in denteni excunente, 

 marginibus rectis ; punctoinbasimandibularum, J ruaculis4 in clypeo, 

 puncto frontali et post-oculari, linea in scapo, fascia bilobata pionoti, 

 macula subalari, 2 scutelli, post-seutello et abdominis segmentorum 

 marginibus anguste, tibiis tarsisque, fiavis ; antennis subtus ferragi- 

 neis ; alis hyaliuis, apice fusco nebulosis. 



fOdyn. dcedaleus Harris Cat., 1833, p. 5S9, undescribed. 

 ii i, iigris Sauss. Revue Zool., IX, 1857, 273. 

 fOdyn.pertinax^ >w<<. Et. Vespides, III, 1854, 216, 108, £. 

 Odyn. cervus Sauss. Rev. Zool., X, 1858, 1G5. 



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



£ . Total length, 8 mm.; wing, tj mm. 



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

 pre--ei|, not cylindrical. Clypeus pyriform; coarsely punc- 

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

 in-- 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 raesothorax often presenting a little smooth 

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

 acute] arcuate on its posterior border. Metathorax having its 

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

 two plane inclosures of a pentagonal shape, very angulate, 



1 Small male, not easy to determine. 



