AMERICAN HYMENOPTERA. 373 



DESCRIPTIONS OF SEW SPECIES OF NEOTROPICAL 

 HYMENOPTERA. 



BY P. CAMP: RON. 



SPHEGID.E. 



Trypoxylon nigrispinis sp. nov. 



Black, except for an obscure white spot ou the base of the hind tibise; tbe face 

 and clypeus thickly covered with silvery pubescence; tbe wings hyaline, very 

 iridescent, the nervures and stigma black. £ • Length 5 mm. 



Front and vertex opaque, minutely, closely punctured, the former with an 

 obscure furrow below the ocelli ; the hind ocelli are separated from the eyes by 

 half the distance they are from each other; the anterior is separated from the 

 posterior by a greater distance than these are from each other. Clypeus not 

 keeled. Apical half of mandibles brownish. Temples covered with silvery 

 pubescence. Mesonotum closely, minutely punctured. The central area on the 

 metanotum is not very clearly sepaiated and is closely, finely, transversely stri- 

 ated and slightly depressed ; the apex has an oblique slope, has a wide, shallow 

 furrow above. Metapleurae distinctly, closely obliquely striated ; the others 

 smooth and shining ; the striated part is bounded below by a stouter keel. First 

 abdominal segment of almost equal width, heing only slightly narrowed towards 

 the base; it is about one-third longer than the 2nd ; the segments become slightly 

 gradually thicker towards the apical ; the basal 3 segments united are as long as 

 thethorax. Legsslender, the hind tibia? not dilated ; the long spur of hind tibiae 

 reaches to the middle of the metatarsus. Apex of radial cellule lanceolate, grad- 

 ually narrowed to a point; the apex of cubitus and lower part of transverse 

 cubital nervure are roundly dilated outwardly. Mandibles unidentate. Pygidial 

 area sharp-pointed. 



Hab. — Mexico. 



This little species conies nearest to T. rugifrcns Cam. from Vera 

 Cruz; the two may be separated thus : 



Base of median segment strongly obliquely striated ; calcaria pale; the transverse 

 cubital nervure forming with the cubitus a straight oblique angle, 

 the apical abscissa of the cubitus straight, oblique, .rnjjifroiis Cam 



Base of median segment weakly transversely striated ; calcaria black; apex of 

 cubitus and lower part of transverse cubital nervure broadly rounded, 

 dilated outwardly, the apical abscissa rounded nigrispinis. 



The radial cellule in rugifrons is narrower and longer, the radius 

 reaching close to the apex of the wings; the basal abscissa of the 

 radius being about one fourth of the length of the apical ; in nigri- 

 spinis it is slightly more than half the length. 



TBAN AM. ENT. SOC. XXXI. (47*) OCTOBER, 1905. 



