AMERICAN IIYMENOPTERA. 85 



NOTES ON THE POMPILID^ OF NORTH AMERICA, 

 with descriptions of new species. 



BY E. T. C'RESSO^\ 

 [Coininunicated March 11th, 1867.] 

 Genus POMPILUS, Fabr. 

 Head transverse, broiider than the thorax, sometimes transversely 

 compressed, as in fii?. 2 r, (^piir/>i(ripe.ani<, M irise, l^j'ttas and clcr/ioift) ; 

 eyes lateral, oblouii-ovate ; ocelli placed in a triatiji;le on the vertex ; face 

 variable in length and breadth ; clypeus variable in shape, the an- 

 terior margin emarginate, rounded or truncate; antennae convolute in 

 the females, straight, or but slightly bent, and sometimes crenulate (as 

 Figure 1. in Fig. 1) in the males, the length variable in 



^i:*=^'^^^-^~^^'^^^^~^'~^^ different species, inserted in the middle of the 



anterior part of the face, sometimes in broad, rather deep fossae, (spe- 

 cies Nos. 23, 50, 51 and 52). 



Thorax oblong, more or less gibbous in front, and more or less corn- 

 Figure 2. pressed at the sides ; prothoras generally broader 

 «• ^- ^- than long, sometimes oblong-sub(|uadrate, (as in 

 Fig. 2 c = piirpuripentti.s, Mun'se, Icjjdtus and ele- 

 gans), the posterior margin either arcuate (as in 



yy yj^ ff I , Fig. 2 Z*), or more or less angular, (as in Fig. 2 a); 



metathorax generally smooth and rounded above, 

 sometimes, but rarely, rugose, the apex truncate or obtuse. 



Wings : the anterior pair with one marginal and three or four sub- 

 marginal cells, the first submarginal generally as long as the two fol- 

 lowing together, the second and third receiving each a recurrent ner- 

 vure ; the marginal cell varies in shape in different species, sometimes 

 long, and regularly lanceolate, sometimes short, broad, and nearly tri- 

 angular; the second and third submarginals vary much in shape, 

 sometimes in different individuals of the same species, the third is es- 

 pecially variable, being sometimes quadrate, sometimes triangular and 

 sometimes petiolated ; the basal series of transverse uervures are some- 

 times widely dislocated; in some species of the subgenera Priocnemis 

 and A(/enia there are four distinct submarginal cells, the cubital ner- 

 vure extending entirely and clearly to the apical margin of the wing. 

 Legs variable in length and strength, the posterior pair the longest; 

 in the subgenus PompUus all the legs are more or less spinose, and 



