266 Mr. Cameron on 



the pronotum, scutellum, post scutellum, a narrow band on 

 the base of the second abdominal segment, the extreme 

 apex of the petiole, the apical half of the third segment and 

 the extreme apex of the fourth, reddish-fulvous. Legs 

 black ; the anterior tibiae and tarsi obscure testaceous in 

 front. Length 15 mm. 



Cerceris humbertiana (PI. X., f. 16, a, b.) 



In the $ the eyes are parallel. The hinder ocelli 

 are separated from them by a little more than the 

 length of the third antennal joint, and by nearly the same 

 distance from each other. The middle of the clypeus 

 projects considerably, the projection almost truncated at 

 the apex, except that there is a waved projection in the 

 middle ; the sides of the projection are obliquely curved. 

 The lateral hair fringe is dense and golden. The third 

 antennal joint is a little longer than the fourth and attenu- 

 ated at the apex. The puncturing on the top of the head 

 is very deep and coarse, on the thorax it is not quite so 

 strong. The trigonal area of median segment is smooth, 

 shining, and impunctuate, and has very narrow and in- 

 distinct furrow down the middle. Pygidial area bearing 

 large oval punctures; it is a little narrowed and truncated at 

 the apex and has there a golden pile. The petiole is broader 

 than long and rugosely punctured. The other segments 

 bear large, separated punctures of moderate length. 



May be known from the $ of instabilis by the clypeus 

 of the latter not projecting so squarely in the middle ; by 

 the trigonal area being coarsely longitudinally striolated ; 

 by the petiole being much narrower, being clearly longer 

 than broad ; by the yellow band on the vertex, &c. 



Apparently a common species. 



Cerceris emortualis. 

 I should say, judging how very variable humbertiana is, 

 that this will prove to be a variety of the latter. 



