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assigning to their Group a few of those whose claw-structure 

 is nearest to the border line. It is, perhaps, well, therefore, to 

 repeat here the definitions of bifid and appendiculate claws 

 with special application to the requirements of identification 

 in these particular Groups. A typically bifid claw, then, is 

 one in which the basal piece is conspicuously produced at its 

 inner apex into a process more or less perpendicular to the 

 axis of the claw, which process is at least half as large as the 

 process of the apical piece, the whole basal piece being on the 

 external margin much longer than (usually about twice as 

 long as) the apical piece. A typically appendiculate claw is 

 not produced at the inner apex of the basal piece, or is pro- 

 duced into a minute process much less than half as large as 

 the process of the apical piece and very much more slender, 

 the whole basal piece being on the external margin not much 

 longer than the apical piece. Near the border line (in respect 

 of the claws) of Group VIII. are a few species in which the 

 apical piece of the (hind) claws is larger than normal, or the 

 process of the basal piece is scarcely half as large as that of 

 the apical piece. In these possibly doubtful species one at 

 least of the following characters is present in the claws, and 

 is not present in those of any possibly doubtful species of 

 Group VIII. : — (a) The process of the basal piece a wide 

 triangular tooth-like projection, or truncate at its apex (as 

 distinguished from the apex of the whole basal piece) ; (b) 

 the intermediate or front claws (or both of them) notably 

 more typically bifid than the hind claws. The species with 

 hind claws least pronouncedly bifid are, perhaps, ignobilis, 

 Blackb. ; neglectus, Blackb. ; lucidus, Blackb. ; arid us, 

 Blackb. ; and diversiceps, Blackb., but I do not think anyone 

 would find any real difficulty even with them. 



It must be noticed that in order to determine the form 

 of the claw it is necessary to look at it with its compressed 

 surface levelly opposite the eye. Viewed with the outer 

 margin in that position many appendiculate claws appear 

 simple, which, I have no doubt, accounts for the statement 

 of Lacordaire and others that some Heteronyces have simple 

 hind claws. Viewed obliquely from in front, so that the 

 apical piece appears foreshortened, some appendiculate claws 

 seem to be bifid. 



A remark seems desirable on a character occasionally made 

 use of in the tabulation of this and the next Group, viz., the 

 lateral projection of the clypeus, which is not a mere matter 

 of degree, for where it passes the outline of the eye, as in the 

 majority of Heteronyces it does, it is (I think invariably) of 

 more or less angular form, whereas in those species where it 

 does not pass the outline of the eye there is no angulation. 



