ENHYDEIODON. 337 



mammilla is nearly of the same size, but simple. It is this 

 posterior lobe, of which there is no trace in the Otter or 

 Enhydra, that, so far as regards the composition of the 

 coronal, distinguishes the carnassier of Enliydriodoyi so 

 strongly from that of other Oarnivora. In its great features 

 this tooth looks as if made up of three nearly equal conical 

 mammillae disposed in triangle, two occupying the inner side, 

 and one at the outer bearing a lobe at each end. In the 

 larger species^ it has precisely the same form as in the small 

 one, showing it intact from wear, the only difference being 

 that the inner portion is, if anything, larger. The manner in 

 which the ' wear ' of the tooth goes on is seen in all the 

 specimens, the apices of the mammillae being truncated off 

 horizontally, so as to form depressed discs, surrounded by 

 a thick ring of enamel resembling what is shown upon the 

 teeth of old Hyaenas, and on the molars of the Phacochoerine 

 Hogs. We have noticed that the teeth of Enhydra and Lutra 

 do not show a ' wear ' of this sort. 



► 



APPENDIX TO MEMOIE ON ENHYDEIODON. 

 I. — MS. Memorandum by Dr. Falconer, 1845. 



Compared the head of Indian Otter (recent) with four heads in College 

 of Surgeons. It is about half inch longer than any of them; the naso- 

 frontal oblong in Indian ; nearly square in European, or approaching 

 square. In one head, No. 295, of an old animal, it is very square. Post- 

 orbital part of frontals is more elongated and more contracted in Indian, 

 but great difference in this respect in the European. In No. 295 it is 

 very broad and short, wider than long ; while in another, No. 55, from 

 the side cases, the sides converge backwards into a verj' narrow con- 

 traction, half the width of No. 295 ; this is also an old head. 



II. — Memorandum in MS. made at Dr. Jameson's, Suharunpoor, 



Jan. 21, 1841. 



Dimensions of a Loiver Jaw fragment. Enliydriodon. 



Fragment consists of the posterior part of the lower jaw, left side, 

 with the ramus broken off above the base of temporal fossa ; con- 

 dyles, &c., removed. The carnassier tooth and a solitary tubercular 

 are in situ. 



Dimensions. 



luches 

 From the anterior margin of carnassier to the rear of the tuber- 

 cular . . . . . . . . . . . 1'4 



Length of the carnassier . . . . . . . . 1 • 



Width of ditto -4 



Length of tubercular ........ '45 



Width of ditto -3 



Height of jaw to base of carnassier . . . . . . Tl 



Greatest thickness of ditto ....... '5 



• Here and at page 331 allusion is made to more than one species of Enhy- 

 driodon. — [Ed.] 



VOL. I. Z 



