Mr. J. E. Gray on the Hollow-horned Ruminants. 231 



the spiral ridge arises from the hinder part of the inner side of 

 the horns, the front one being obscure. 



The genera of the Antilopea being more numerous are worthy 

 of a more minute examination, considering as I do that it is im- 

 portant to divide these numerous genera into natural groups, 

 more especially as there appears to be a character afforded by 

 the nostrils which has been hitherto overlooked, and which se- 

 parates them into two very distinct and easily recognised sec- 

 tions. This character shows the real position of the Gnu, and at 

 the same time proves that Colonel Hamilton Smith was correct 

 in forming his genus Damalis, though he did not discover the 

 character by which it was best to be defined, and hence placed 

 with it some species that were not truly allied to it ; and it leaves 

 the other Antelopes easily reducible into small groups. 



The Antilopece may be thus divided : — 



I. The Antelopes of the Fields have the nostrils bald within. 



1. The True Antelopes are light-bodied and slender-limbed, 

 with small hoofs and a short or moderate tail covered with elon- 

 gated hairs to the base, and lyrate or conical horns. 



A. Horns moderate, lyrate ; muzzle ovine. 



Saiga. Nose very high, compressed, truncated. Horns white, 

 lyrate. S. Colus. 



Kemas. Nose of male with a dilatation on each side. Horns 

 elongated, compressed, sublyrate. K. Hodgsonii. 



Gazella. Nose tapering, simple. Horns lyrate. Tear-bag 

 distinct. G. gutturosa, G. subgutturosa, G. Dorcas, G. rufifrons, 

 G. Isabella, G. Bennettii, G. Sosmmeringii, G. Dama, G. ruficollis 

 and G. mohr. 



Antilope. Nose tapering. Horns lyrate, elongate. Tear- 

 bag none. A. melampus. 



Cervicapra. Nose tapering, simple. Horns cylindrical, sub- 

 spiral. C. bezoartica. 



B. Horns slender, conical, small. 



Neotragus. Muffle ovine. Crown crested. Tear-bag large, 

 round. N. Saltiana. 



Cephalophus. Muffle bald. Crown crested. Tear-bag a 

 linear glandular line. C. mergens, &c. See p. 163, &c. of this 

 volume. 



Nanotragus. Muffle bald. Tear-bag none. False hoofs 

 none. N. pygmcea. 



Tetracerus. Muffle bald. Horns two pairs. Tear-bag lon- 

 gitudinal. T. quadricornis. 



Oreotragus. Muffle bald. Horns elongate, acute. Tear- 



