Dec. 1896.] Packard: Transformations of Hymenoptera. 159 



acutely so, so that dorsally there are subacute extensions of the thick- 

 ened posterior portion. The terminal segments cylindrical, less con- 

 vex, the terminal or tenth ring cylindrical, not flattened, large and 

 full. Beneath, the rings are very convex. The pleural region not very 

 distinctly marked. Color a beautiful roseate tint. Head long and as 

 narrow as usual, though no more so; full and convex; supra-clypeal 

 piece large, subtriangular, indistinctly marked. Antennal fossa rudi- 

 mentary ; placed rather farther back, or rather the clypeus is so much 

 shorter than usual as' to give it the appearance of being situated farther 

 back. Clypeus short and broad, transversely oblong, base convex, 

 front edge a little concave, as broad as the base ; the sides parallel, 

 acutely convex. Labrum large chitinous, transparent, as broad as the 

 clypeus, bilobate, with a distinct median line. Mandibles rather slen- 

 der,_ long, incurved, very acute. Maxillae cylindrical, 2-jointed, tip or 

 rudiment of the palpi minute. Labium much as usual, flattened, cylin- 

 drical, ending in a transverse chitinous line, being the rudiment of the 

 lingua? en each side of which are the minute rudiments of the palpi. 



Described from living specimens. 



Pupa. — Head full, convex in front, much as in the adult ; ocelli 

 prominent; papillae acute. Antennae folded over the base of the nar- 

 row, acute, curved, prominent mandibles as described in Cetfwnus, and 

 reaching to the first pair of trochanters. Lingua much shorter than in 

 Cemonus ; the palpi very small and slender. The fore legs are very 

 slender, the tarsi just reaching to the middle trochanters, while the hind 

 tarsi reach to the middle of the abdomen. The ovipositor is exserted, 

 the wings covering the middle tibiae and femora. Length, .15 inch. 



It differs from Cemonus in generic characters observed in the imago. 

 The palpi are much smaller ; lingua and maxillae much shorter, and 

 mouth-parts generally much weaker. The head is more ovate, full and 

 convex in front, where it is sunken and depressed in Cemonus. The 

 antennae are much slenderer, and the abdomen longer and slenderer, 

 as the hind legs scarcely reach to the middle, where in Cemonus they 

 pass beyond. The mandibles are much more slender, their tips being 

 more acute. 



Cemonus inornatus {Say'). 



Larva. — Body oblong, long, and greatly flattened, the lateral 

 ridges of that segment very large, broadly triangular, becoming larger 

 and more pointed towards the end of the body. The body does not 

 narrow any until the nth segment, when it suddenly tapers off. Above* 



