30 Dr. Falconer arid Capt. Cautley on additioiial 



As in all other tribes of animals in which the species are 

 very numerous, and closely allied in organization, it is next 

 to impossible to distinguish an individual species in the Qua- 

 drumana from a solitary bone. In the fossil, too, the effects of 

 age have worn off those marks in the teeth by which an ap- 

 proximation to the subgenus might be made. It very closely 

 resembles the Semnopithecus Entellus in form, and compara- 

 tive dimensions generally. The differences observable are 

 slight. The symphysis is proportionally a little deeper than 

 in EntelluSi and the height of the body of the jaw somewhat 

 greater. The chin, however, is considerably more compressed 

 laterally under the second molar than in the Entellus, and 

 the first molar more elongated and salient. So much of the 

 canine as remains has exactly the same form as in the Entel- 

 Itis, and its proportional size is fully as great. As shown by 

 the dimensions, the jaw is much larger than in the full-grown 

 Entellus: in the former the length would have been about 

 5*3 inches, while in the latter it is exactly 4 inches. The 

 fossil was a species of smaller size than the animal to which 

 the specimen described by Messrs. Baker and Durand be- 

 longed, but less so than it exceeds the Entellus. 



Our limited means for comparison, restricted to two living 

 species, besides the imperfection of the fossil, and the few 

 characters which it supplies, do not admit of affirming whether 

 it belongs to an existing or extinct species ; but the analogy 

 of the ascertained number of extinct species among the Sewa- 

 lik fossil mammalia, makes it more probable that this monkey 

 is an extinct one than otherwise. There is no doubt about 

 its differing specifically from the two Indian species with 

 which we have compared it. 



The next specimen is shown in fig. 5. [PI. I.] It is a fragment 

 of the body of the right side of the lower jaw, containing the 

 four rear molars. The teeth are beautifully perfect. It had 

 belonged to an adult, although not an aged animal, the last 

 molar having the points a little worn, while the anterior teeth 

 are considerably so. The dimensions, taken along with age, 

 at once prove that it belonged to a different and smaller spe- 

 cies than the fossil first noticed. 



The dimensions are as follow : — 



