TUPAIID^. 117 



Tlie canine lias the greatest vertical extension o£ all the teeth in the lower jaw, 

 and the deciduous tooth has a shorter and more obtuse crown than the permanent 

 tooth. It is laterally compressed, and its posterior margin, viewing it in profile, has a 

 slight swelling near its base, corresponding to the talon of the second premolar, the 

 area or margin above it, to the point of the tooth, being concave. The anterior 

 margin is rounded forwards to the point, which is almost in the same line with the 

 posterior margin, and is directed forwards and upwards. The permanent tooth lies 

 internal to it, resting upon the base of the fang, or nearly so. 



The crown of the third incisor, as, to a certain extent, the crowns of the canine 

 and first premolar, is set on obtusely to the fang, the latter being directed down- 

 wards and backwards, the former upwards and forwards to a greater degree than the 

 fang is in its course. The tooth is laterally compressed and its crown rounded; its 

 posterior margin convex from before backwards and almost straight ; but where the 

 latter joins the fang an angular point is formed corresponding to the angle in the 

 canine and first premolar, and to the talon of the second premolar. Its permanent 

 tooth is very difficult to demonstrate ; but I believe I have detected it lying at its 

 base externally, on the same plane as itself. On the internal aspect of the jaw the 

 young permanent canine and second incisor are so close, and the latter is placed so 

 obliquely from behind forwards, that there is no room for it in that direction, and 

 it has therefore to be sought for by removing the bone from the outer sm'face of 

 the jaw. 



The second incisor has its anterior or external surface somewhat convex from 

 behind forwards with its lateral margins parallel and abruptly rounded off to the points. 

 The internal surface, concave from before backwards, has a convex longitudinal ridge 

 with a well-marked groove in the same direction external to it, and a more indistinct 

 one internally. The base of the crown forms an angular prominence externally with 

 the fang, from the circumstance that the crown is placed slightly obtusely to the root 

 of the tooth. The fang is long and reaches back to nearly on a line with the 

 posterior border of the symphysis. The permanent tooth lies internal to it, and 

 above, it is separated from the permanent first incisor by a longitudinal, or nearly 

 longitudinal, osseous ridge ; it is chiefly distinguished from the deciduous tooth by 

 its larger size. 



The first deciduous incisor is a narrower and more pointed tooth than the pre- 

 vious one, but of the same structure, and is distinguished from its permanent tooth, 

 which lies internal to and resting on it, by its greater size.^ 



^ The specimen -with abnoi-mal dentition was received from Darjeeling, and is an example of T. helangeri. It is 

 young, and on laying bare the roots of the teeth of the upper jaw, I have been able to demonstrate which are the 

 superfluous teeth. None of the permanent teeth, except the three molars, are through the gum. As the dentition is 

 diiferent in the two sides, I shall describe them separately. On the right side, above, there are ten teeth, the abnormal 

 tooth being small, partaking of the character of a diminutive canine wedged in between the deciduous canine and the 

 deciduous first premolar. The young permanent teeth are in their positions in front and at the base of their respective 

 teeth, but no young tooth exists to take the place of the superfluous one. On the left side no less than eleven teeth occur, 

 one anterior to the canine and one behind it. These teeth are placed at equal distances from each other and are of equal 

 size, and all resemble diminutive canines. The middle tooth is the true canine, as is shown by the presence of the young 

 permanent tooth in front of it. The abnormal teeth on either side of the canine are not represented by any young 

 tooth, so that the normal dentition would be attained in the adult state. 



