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of the lateral margin of the hind coxae carinate and sub- 

 spiniform. The last-mentioned character is not present in 

 any species that I have placed in the aggregate BB. The 

 normal condition of species of BB is: hind coxae much shorter 

 than metasternum, and not more nearly equal in respect of 

 length to the metasternum than to the 2nd ventral segment 

 (in many species very little longer than the 2nd ventral seg- 

 ment), the exposed part of the 1st ventral segment half (or 

 even more than half) as long as the 2nd ventral segment. 

 The only departure known to me in BB from the above 

 described condition sufficiently marked to be worthy of men- 

 tion is in a very small number of species (e.g., H . fumatus, 

 Er.) in which the hind coxae are unduly longer than the 2nd 

 ventral segment, but these insects have an unusually long 

 metasternum (very considerably longer than the hind coxae) 

 and also have the 1st ventral segment largely exposed. 



The aggregate B of AA, it will be observed, is divided 

 into two sections (C and CC), distinguished by the elytra 

 being either very closely punctulate or notably less closely 

 punctulate — in the former section 20 punctures from the 

 suture not passing the middle of the elytra. The only species 

 that can be considered near the border line between these 

 sections is furvus, Blackb. (of the aggregate CC), in which 

 about 17 elytral punctures from the suture reach the middle. 



The pronotum of many species of Heteronyx is fringed 

 in front with long erect hairs, and I believe their presence 

 or absence to be of value in distinguishing species, but as 

 the hairs in question are very easily rubbed off, I have not 

 considered it wise to make much use of the character. The 

 pronotum and elytra are usually (probably always in fresh 

 specimens) fringed laterally also, but I have not found that 

 character to be of value for distinguishing species. 



It will be noted that in this Group I have described the 

 claws only of the hind tarsi. In all the species all the claws 

 are appendiculate, I believe (except in a few species whose 

 front claws are described), but the other characters ascribed 

 to the hind claws are not in all cases exactly reproduced in 

 the other claws. 



In some species of this Group (and in some instances in 

 other Groups) individual specimens have feeble indications of 

 a longitudinal channel on the pronotum. Its distinctness is 

 certainly variable within the limits of a species, and (in some 

 species, at any rate) is dependent on the degree of maturity 

 of the specimen. It does not seem to be a reliable character 

 for diagnosis. 



