Patton.] . 884 [January 21, 
semicircular, truncate at the apex, the truncation bounded by a pair ~ 
of stout, slightly divergent, truncated processes, the labrum with a 
broad thickened margin separated by an impressed line; labrum of 
the male short, evenly rounded anteriorly and unarmed, the epi- 
pharynx extending beyond it as a broad membranous margin sub- 
angularly rounded at the apex. Labrum in both sexes ciliate with 
long bristles on each side and without any median carina. “Mandi- 
bles of the female with two stout teeth on the inner side, the proxi- 
mal tooth the larger. Mandibles of the male with only 6ne tooth 
within. Marginal cell not extending beyond third submarginal. 
Tarsal claws bidentate, second tooth as large as the first or larger; 
a long curved bristle between the claws in addition to the two 
smaller and straight ones. Anterior tarsi of the female ciliated ex- 
ternally with long bristles. Petiole a little longer than the posterior 
coxae; abdomen convex, the tip pointed in the female. 
This American group differs in some respects from the Old 
World group of which the ‘type, H. crudelis Sm., is said to have the 
clypeus notched in the middle of the margin. The characters given 
above must, therefore, be understood to apply to the American spe- 
cies only. Until the typical form is more carefully described we 
cannot safely propose a new genus for our species. 
PRIONONYX Dahlb. 
Type: P. Thomae (Fabr.) Dahlb. 
Clypeus of the female produced in its whole width; a deep notch 
in the middle, above which is an elongated depression. Clypeus of 
the male not so broadly produced, slightly sinuated anteriorly. 
Labrum of the female narrowed anteriorly and bilobed, the lobes 
ciliated with long bristles, and separated by a large square sinus; 
in the median line a short prominent carina which extends as a 
short tooth into the sinus. Labrum of male narrowed anteriorly, 
. the narrowed portion ciliated with long bristles, the anterior border 
broadly sinuate, the sinus not ciliated. Mandibles of the female 
with two teeth on the inner side, the proximal tooth the smaller, 
yet larger than the corresponding tooth in Sphez. Marginal cell not 
extending beyond the third submarginal. Tarsal claws with five 
teeth beneath, the outer teeth the largest, the basal tooth very 
small, but distinct; a long curved bristle between the claws in addi- 
tion to the two smaller and straight ones. Anterior tarsi of the 
