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both in the inward bending of that angle, which is remarkable for the 

 great longitudinal extent along which the inflection takes place : most of 

 the inflected angle has been broken away, but enough remains to de- 

 monstrate a most instructive and interesting correspondence between the 

 present fossil and the characteristically modified lower jaw in the marsu- 

 pial animals. In pursuing the comparison of the Australian pachydermal 

 fossil with the Mastodon and Elephant, we may next observe that the 

 alveolar process on the inner side of the base of the coronoid, behind 

 the last molar, is as well developed as in the Mastodon; a similar angular 

 production of this part exists in the Wombat and Kangaroo. The 

 vertical extent of the outer concavity of the coronoid process is greater 

 in the Australian fossil than in the jaw of the Mastodon and is less clearly 

 defined below, in which respect the Notothere resembles more> the Ele- 

 phant. The dental canal commences by a foramen penetrating the ridge 

 which leads from the condyle to the post-molar process, and apparently just 

 below the condyle, as in the Elephant, but it is relatively much smaller : 

 it does not communicate with any canal leading to the outer surface 

 of the ascending ramus, as in the Wombat and Kangaroo ; but this 

 external opening is not present in all Marsupialia. 



The anterior outlet of the dental canal is smaller than in the Mastodon 

 and more anterior in position, and so far resembles the Elephant. The 

 number, and apparently the form of the teeth, approximate the Austra- 

 lian Pachyderm more closely to the Mastodon than to the Elephant ; 

 but the equal size of the last and penultimate teeth, which had the 

 same number of divisions of the crown, are points in which the Noto- 

 therium still more nearly resembled the Diprotodon, the Tapir and 

 Kangaroo. 



In the general shape of the jaw, however, the Nototherium differs 

 widely from all existing Marsupials and all known ordinary Pachyderms, 

 and in the chief of these differences it resembles the lower jaw of the 

 Proboscidians. It resembles these, however, in common with the Wom- 

 bat, in the forward slope and curvature of the posterior margin of the 

 ascending ramus extending from the condyle to the angle, in the inward 

 production of the post-molar process, in the position of the base of the 



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