182 ALLOCHBOMA. 



to dilatation ; the basal joint is long, and incrassated towards the apex ; 

 the second short and ovate ; the third attenuate, and always longer 

 than the first ; the fourth varies in length in different species, some- 

 times it is shorter than (but more frequently equal in length to) the 

 third and fifth ; the rest of the joints are robust and generally sub- 

 incrassated. 



Eyes globose, lateral, situated at the base of the head. 



Head much narrower than the thorax, hardly produced in front, 

 depressed, frequently at right angles to the plane of the thorax. 



Thorax transverse (very rarely if ever quadrate), broader than the 

 head ; the anterior angles are depressed and distinct (not obsolete or 

 rounded, as in the gemis Rhinotmetus) ; the sides are marginate and 

 for the most part parallel ; the surface is generally broad and flat 

 rather than subcylindrical, glabrous, or in some cases sparingly 

 clothed with obsolete pubescence. 



Scutellum well- developed, triangular, situated in the same plane as 

 that of the elytra. 



Elytra broad, cylindrical, and abbreviated; always broader and 

 more robust than the thorax ; in some species antemedially trans- 

 versely depressed ; the surface is punctate-striate, glabrous or finely 

 pubescent, and generally brightly coloured. 



Legs robust and sufficiently elongate. The anterior femora sub- 

 cylindrical. The tibiae are inflected at the immediate base, straight, 

 unarmed, longitudinally grooved in front. The tarsi are broad and 

 short ; the first and second joints are subequal, and in form trian- 

 gular, in most species broader than the apex of the tibiae ; the third 

 joint is of still greater breadth, and deeply bilobed ; the terminal 

 joint is slightly incrassated towards the apex : the claw is armed at 

 its inner surface with a very distinct tooth. The posterior femora 

 are incrassated and ovate. The tibial are distinctly incurved at the 

 base, straight, and longitudinally grooved along their posterior sur- 

 face : the margins of this groove are in no instance serrated or armed 

 with a tooth ; for the most part they are straight, rarely in outline 

 even sinuate : the apex of the tibia is dilated and obliquely truncate : 

 the socket for the insertion of the tarsus is unarmed laterally (as is 

 the case in other genera) by comb-like teeth; it is terminated by 

 two strong and very distinct spurs. The tarsus is short and attenu- 

 ated ; the two basal joints are subdilated towards their apex; the 

 third is circular and somewhat broader ; the fourth broadly inflated : 

 the terminal claw, like the anterior, is armed at its inner surface 

 with a basal spur. 



This genus may without difficulty be separated from those adjoining 

 it. In general faciea the species composing it are shorter and more 



