228 MESSRS. T. BLACKBURN AND P. CAMERON ON THE 



Mr. Smith. As the female was described before the male, 

 and the latter (as compared with most of its Hawaiian 

 congeners) does not deserve the name C. denticornis, the 

 species had better be called C. mandibularis . 



The space between the eyes is exceptionally narrow and 

 strongly concave. The head is very finely and smoothly 

 punctured, with scarcely any traces of strigosity. The 

 eyes are facetted finely in the male, by no means finely in 

 the female. The hind body is narrow and not at all 

 strongly rounded laterally. The ventral segments of the 

 male resemble those of the same sex in C. affinis. 



This species varies in colour. I have a male in which 

 there is no yellow tint on the postscutellum. 



40. Crabro poli/nesialis. 



Crabro 23olt/nesiaUs, Cameron, Trans. Ent. Soc. 1881, p. 562. 



Mr. Cameron^s description requires no supplement be- 

 yond a word as to the differences between this and other 

 species (not in Mr. C/s possession), and a remark on the 

 male. 



The eyes are rather close to each other in front, though 

 a little more separated than in C. mandibularis, Smith, 

 and are quite strongly facetted, much more so than in 

 C. affinis. The hind body is similar in shape to that of 

 C. mandibularis. 



In the male the antennal sexual characters are almost 

 as in C. mandibularis, while the ventral depression extends 

 quite evidently from the middle of the third segment to 

 the apex. 



Hab. Mauna Loa, Hawaii^ at an elevation of 4000 feet. 



41. Crabro abnormis. 



C. abnormis, sp. nov. (^ . Minus nitidus, pubescens^ cre- 

 berrime subrugoso-punctatus, niger ; clypeo fronteque 



