58 Zoological Society, 



the nostrils are surroinided by a distinct narrow callous edge ; the 

 callosity occupies the space between the nostrils and a narrow central 

 band down to the lips ; the body is covered with very close soft 

 hair, and on the haunches and other parts where the hair is longer, 

 it retains its softness, but approaches to the quill-like character of the 

 Roebuck ; the upper part of the body is ochraceous yellow, the lower 

 part paler and whitish ; the head is paler yello)?¥JL§h^j,^4iJtei]wi;s 

 on the forehead and face are tipped with whitish. _1. , j\ og^; ^q-]/i ^ 



1,, The foUowmg paper was read :-r. [y^i,;/,^ ^ihRCi odi yd nworf« «^: 



i. On the variation in the Teeth of the Crested Seal, 

 Cystophora cristata, and on a new species of the 



GENUS FROM THE WeST InDIES. By J. E. GrAY, EsQ., 

 ' F.R.S. ETC. 



In a paper which I lately communicated to the Society on the 

 genus BradypuSy I drew their attention to some variations in the 

 form of the lower jaw, which were not accompanied by any appre- 

 ciable difference in the external appearance of the specimens ; I now 

 wish to bring before the Society some variations which I have ob- 

 served in the teeth of the different skulls of the Crested Seal which 

 I have received from Greenland. I consider it of more importance 

 to record these variations, as the formation of the teeth in the family 

 of Seals has been considered as affording one of the best characters 

 for the distinction of the species. 



Several zoologists have considered the Crested Seal of the northern 

 and the Proboscis Seal of the southern hemisphere as belonging to the 

 same genus ; but though there are several characters which are com- 

 mon to both, they are very easily distinguished. 



The grinders of the Proboscis Seal are only slightly plaited on the 

 crown, all have only simple subcylindrical roots, which are cylindrical 

 in the young animal, and enlarged, short, and clavate in the adult 

 specimens. The grinders of the Crested Seal, on the contrary, are 

 rather tubercular and very closely and strongly plaited on the 

 crown, and this character is seldom obliterated by age, and in most 

 of the skulls the 4th and 5th grinder of both jaws have two roots, 

 and the root of the 3rd grinder is partially divided on the outer side ; 

 but in some adult skulls (probably belonging to the males ?) the roots 

 of the 4th and of the 1st, 2nd and 3rd grinders are enlarged and 

 simple-rooted, and in one young skull the 4 th grinder is also simple- 

 rooted. 



I shall proceed to give the variations to be observed in the follow- 

 ing skulls, all received from Greenland : — 



1. No. 332 b. in Brit. Mus. Cat. — The skull of an adult or aged 

 specimen : the crowns plaited, the roots of all the grinders enlarged 

 and short, club-shaped and simple, separated from the crown by a 

 narrow collar. 



2. No. 332 a. — Skull of adult : the crown worn ; the root of the 1st, 

 2nd, 3rd, 4th, rather enlarged, oblong club-shaped, rather elongate, 

 the root of the 5th grinder compressed, of the left side simple, of the 



