147 



the larger proportion of cement which fills the interspaces of the plates, 

 and the enamel is much less strongly plicated ; in this latter character it 

 varies remarkably from the preceding specimen. 



Locality unrecorded. Hunterian. 



610. A right upper molar of a Mammoth, wanting a few lamellae from either 



extremity. The grinding surface, which is six inches in length, presents 

 the summits of thirteen transverse plates ; the primitive form of these 

 component lamellae is well displayed at the posterior part of the grinder ; 

 their free margins are divided into three processes, the middle one much 

 longer and broader than the lateral ones, the apex of the middle process 

 is itself subdivided into smaller mammillae ; in some of the plates one 

 of the lateral processes inclines forwards towards the interspace dividing 

 it from the next plate, by which an alternating disposition of the folds of 

 enamel is presented, when their apices are worn down and before the 

 abrasion has extended to the common uniting base. 



Locality unrecorded. Hunterian. 



611. A left upper molar of probably the same Mammoth. The grinding sur- 



face, which is six inches and a half in length, includes fourteen plates. 

 These are thin and broad, very slightly dilated near the middle, as in the 

 preceding specimen. 



Locality unrecorded. Hunterian. 



612. A left upper molar of a Mammoth : it is nine inches long, and includes 



twenty-five plates, fifteen of which had come into use. The lateral 

 divisions of the summits of the transverse plates have been unequally 

 inclined forwards as in the preceding specimens, occasioning in the 

 posterior part of the tooth, where they have not been worn down to 

 their common uniting lamellar base, alternating lateral folds of enamel. 

 From the bed of the Thames. Mus. Parkinson. 



613. The remnant of a nearly worn-out molar of a Mammoth, the crown of 



which has been abraded by mastication to the common uniting dentinal 

 base of the anterior lamellae, and in which only the lateral half of the 



u 2 



