•JS Journal New York Entomological Society. [Voi. v. 



are more exserted and prominent, the last tergite being much more pro- 

 duced than in Vespa. The nervous system is nearly the same in the 

 middle of the body, but owing to the shorter segments the ganglia are 

 nearer together, and each ganglion is opposite each suture ; the size of 

 the ganglia and of the cords are the same, but the ganglia appear to be 

 a little farther separated than in Vespa, in the specimens examined. 



The head is very large, round, short and broad, full, convex above. 

 The eye-slits are long, narrow, oblique and prominent. The antennal 

 tubercles are flat, depressed, large and conspicuous, and are placed on 

 each side of the clypeus and in a line with the anterior or lower end of 

 the eyes. The clypeus is large, very regularly equilaterally triangular, 

 the apex or posterior portion separated by a slight suture from the ante- 

 rior and much larger portion ; the front edge is straight and aligned with 

 the squarely docked front edge of the side of the head. Labrum very 

 broad and short, nearly as broad as the clypeus is long; the front edge 

 is straight, the sides well rounded ; rounded, swollen, full and very prom- 

 inent at the end. Mandibles broad, triangular, very acutely bidentate, 

 much shorter and broader at base than in the Apidse, very convex on the 

 outer side. Maxill?e large, full, swollen, with two small corneous tu- 

 bercles on the interior next the mouth. Very full and bulging exter- 

 nally. Labium well separated from the mentum by a distinct suture, 

 with two terminal tubercles. Mentum broad, low, triangular, not quite 

 reaching to the outer side of the maxillje, but nearly as broad as the 

 head. 



It differs from the larva of Vespa in having the antennal tubercle a 

 little more approximate, the clypeus more regularly triangular and more 

 distinct, while the labrum is very much larger and excessively swollen. 

 The mandibles are very different from those of Vespa, being bi- 

 dentate, very acute, broad at base, triangular, while in Vespa they are 

 tridentate, oblong, and as wide at the tip as at the base, the teeth being 

 rather equal and blunt, while the mentum is not prominent. The en- 

 tire head is freer from the body in Foiistes, and harder, more corneous 

 than in Vespa. 



Both Foiistes and Vespa larvae differ from those of Botnbiis and 

 Apidse in general in having the clypeus and mouth-parts larger ; by the 

 antennal tubercles being more distinct, by the presence of the eye-slit, 

 by the larger mandibles and maxillae, while the entire head is larger in 

 proportion to the rest of the body, and the surface of the segments are 

 smooth. The end of the body is more acute, and the lateral ridge less 

 marked. (In the larva of 7'<?w/////'i', the segments are more thickened 



