FOSSIL MAMMALIA. 57 



perfect preservation in the fossil state. But five crania have 

 been sufficiently preserved, to which we may add that of the 

 Siberian skeleton above mentioned, to determine the characters. 



The first striking difference is the excessive length of the 

 alveoli of the tusks, being found in one instance to be triple 

 that of those in the Indian or African elephant of the same 

 dimensions. Also the triturating face of the molars, instead 

 of meeting the alveolar ridge, must have cut the tube of the 

 alveolus at one-third of its length. This difference, as we shall 

 see, accords with the form of the lower jaw, and must have 

 necessitated a different conformation in the trunk of the fossil 

 elephant : for either the points of attachment for the muscles 

 of the trunk were the same as in the living species, that is, the 

 upper part of the nose, and the lower edge of the alveoli of the 

 tusks, which would make the basis of this organ three times 

 as thick in proportion, or the attachments were totally different, 

 and then the whole structure must have been totally different. 



The zygomatic arch was differently figured; the post- orbital 

 apophysis of the os frontis longer, more pointed, and more 

 crooked ; and the tubercle of the os lachrymale thicker and 

 more projecting. 



These differences were first established upon a drawing of a 

 cranium, by Messerschmidt, and have been since verified on 

 several others. 



Another difference not less authenticated, and which accords 

 with those of the lower jaw, is the parallelism of the molars. 

 As to the lower jaws, in the Indian and African species, the 

 lower teeth are converging forward, like those above. The 

 canal, therefore, is hollowed in the middle, and long and nar- 

 rowed at the anterior point of the jaw. 



The teeth in the fossil jaws are nearly parallel. The canal, 

 therefore, is wider, in proportion to the total length of the jaw. 

 This canal is also much shorter in the African and Indian 

 species, for the alveoli of the tusks do not descend below the 

 extremity of the lower jaw, which is consequently advanced 



