314 



Genus Nototherium* : 



1505. The right ramus, with the symphysis of the lower jaw, of the Nototherium 

 inerme, Owen, a quadruped apparently manifesting another pachydermal 

 modification of the marsupial type. 



The dentition in the present jaw consists of molar teeth exclusively, 

 four in number, which increase in size as they approach the posterior 

 part of the series : a small portion of the anterior end of the symphysis 

 is broken away, but there is no trace there of the socket of any tooth, and 

 it is too contracted to have supported any tusk or defensive incisor. The 

 length of the jaw is eleven inches : the molar series, which commences one 

 inch in advance of the posterior border of the symphysis, is six inches in 

 extent ; each tooth is implanted by two strong and long conical fangs, 

 the hindermost being the largest, and both being longitudinally grooved 

 upon the side turned to each other. The first tooth is wanting, and the 

 crowns of the rest are broken away : the base of the third remains, which 

 gives an indication of a middle transverse valley, which most probably 

 separated two transverse eminences. This jaw resembles that of the 

 proboscidian Pachyderms in the shortness of the horizontal ramus ; and 

 of the Elephant more particularly in the rounding off of the angle, and 

 in the convex curvature of the lower border of the jaw from the condyle 

 to the symphysis, and also in the smaller vertical diameter of the sym- 

 physis, and the more pointed form of that part. It resembles the jaw of 

 the Elephant in the form, extent and position of the base of the coronoid 

 process ; but it differs from the Elephant in the concavity on the inner 

 side of the posterior half of the ramus of the jaw, which is formed by 

 an inward inflection of the angle : this concavity extends forwards beneath 

 the sockets of the last two molar teeth. It differs from the Elephant in the 

 greater flatness of the outer part of the angle of the jaw, in which respect 

 it more resembles the Mastodon. In the extent of the angle of the jaw 

 it is intermediate between the Mastodon and Elephant. It differs from 



* votos the south, Qtjpiov beast. 



