350 Zoological Society. 



though he compares it in the note above quoted with F. Cuvier's 

 figure of the genus Acanthion, it differs from that figure in most im- 

 portant characters ; while the skull which Brandt figures for that of 

 Hystrix cristata very nearly resembles F. Cuvier's figure above re- 

 ferred to, which represents, according to the characters pointed out 

 in this communication, what I regard as the genus Acanthion. 



Having had the opportunity of comparing the various skulls and 

 skeletons of the species of this genus contained in the British Mu- 

 seum with the skulls of the Indian species in the collection of Colonel 

 Cautley, and with the three skulls in the collections of the Zoological 

 Society, I have been induced to make the following communication 

 to the Meeting, as containing the results of this examination, and 

 with the hope of calling the attention of the Members to the neces- 

 sity of further attention to this hitherto neglected genus. These 

 skulls form themselves into three groups, and that I may not encum- 

 ber science with new names, I have used the three already proposed 

 by the brothers Cuvier, though the characters I have given for the 

 genus Acanthion may not be such as M. F. Cuvier had in his mind 

 when he formed the division. 



Synopsis of the Genera. 



I. Tail short ; skull convex above ; the nasal and intermaxillary bones 

 large to (or to behind) the front edge of the orbit ; the (upper) grinders 

 all with a fold on the inner side. 



1. Hystrix. The intermaxillary broad and truncated, and as wide 

 behind as before. The grinders oblong, longer than broad, with 

 one very distinct fold on the inner and three or four on the outer 

 side. 



2. Acanthion. The intermaxillary triangular, tapering behind ; 

 the grinders subcylindrical, not longer than broad, with a distinct 

 fold on the inner and two or three on the outer side. 



II. Tail elongate, tufted at the end ; skull nearly flat above ; the nasal 

 and intermaxillary bones short, not nearly reaching to the front of 

 the orbits. Intermaxillary narrow, truncated behind; the front 

 (upper) grinders (and perhaps all but the last) without any fold on 

 the inner side. 



3. Atherura. 



1. Hystrix. 



Tail short ; crown and nape crested ; spines subcylindrical, striated ; 

 the skull very wide, swollen, convex above; the nasal and intermaxilla- 

 ries large, reaching to the line even with the front edge of the orbit. 

 The intermaxillaries very large, broad, oblong, as wide behind as 

 before, and' truncated behind ; the palate wide between the grinders ; 

 the grinders oblong, longer than broad. The development of the face 

 is produced by the dilatations of the hinder part of the intermaxillary 

 bones. 



1. Hystrix cristata, Linn., &c. (Crested Porcupine). 



H. hirsutirostris, Brandt, Mim. Petersb. 1835, 375, t. 8. f. 3—6. 



Black ; spines of the sides greyish, softish, subcylindrical ; of the 

 back thick, tapering, with several black rings and a moderate white 



