124 HTMENOPTEEA. 



This well-marked species is a close ally of C. curvicornis, but is larger and stouter, 

 and, if anything, more pilose ; the apex of the clypeus (comparing the males) is trans- 

 verse, with a tooth in the centre; the terminal antennal joint is not hooked; the 

 scutellum and metanotum are not yellow ; the hind tibiae are without black, &c. 



27. Cerceris aCOlhua. (Tab. VIII. figg. 2, head ; 2 a, apex of clypeus ; 2 b> 

 pygidium ; 2 c, hypopygium ; 2 d, antenna, S .) 



Cerceris acolhua, Saussure, Reise d. Novara, Hymen, p. 90 (c?) 1 . 



Hal. Mexico, Chapultepec 1 . 



28. Cerceris CUrvicomis. (Tab. VIII. figg. 3, antenna, S ; 3 a, male organ.) 



Nigra, dense fusco-pilosa, facie, scapo subfrus, linea pronoto, scutello, metanoto, maculis 2 parvis petiolo,. 



abdominis segmentis marginibus pedibusque flavis ; femoribus tibiisque posticis nigris ; flagello anten- 



narum fulvo ; alis fumato-byalinis, apice fusco, nervis stigmateque croceis. 

 Long. 15 millim. 



Hal. Mexico, Presidio de Mazatlan (Forrer). 



Very similar in coloration and size to C. acolhua. It differs, however, in having a 

 yellow wedge-shaped mark over the antennae ; the scutellum yellow ; the hind tibiae 

 black, broadly yellow at the base ; the antennae fulvous beneath ; the band on the 

 pronotum almost complete ; the entire head and body much more densely covered 

 with long fuscous hair, and also more opaque and much more strongly punctured, espe- 

 cially the thorax and abdomen ; the apex of the clypeus instead of having a round 

 broad lobe in the centre is there much narrower, being almost tridentate ; the hinder 

 ocelli separated from each other by almost a greater distance than they are from the 

 eyes (the opposite being the case in C. acolhua) ; the wings at the apex much more 

 clearly infuscated ; the heart-shaped area of the median segment coarsely punctured, 

 not striolate ; and, lastly, the terminal antennal joint much more deeply curved or 

 hooked, and longer than the penultimate. The eyes are parallel and broader than in 

 C. acolhua, the face in C. curvicornis being thus narrower. 



1 29. Cerceris hebes. (Tab. VIII. figg. 4, d ; 4 a, antenna, 6 ; 4 5, clypeus ; 

 4 c, pygidium ; 4 d, hypopygium.) 

 Long. 12-13 millim. 



Eab. Mexico, Chilpancingo in Guerrero 4600 feet (H. H. Smith). 



Eyes slightly diverging beneath. Ocelli almost in a triangle ; the posterior pair 

 separated from the eyes by about the length of the second and third antennal joints 

 united, and by a slightly greater distance from each other. Clypeus flat, slightly 

 hollowed in the middle near the apex, which is produced into a broad triangular blunt 

 point. Antennal tubercle acute, the broad part at the apex. The third antennal 



