Archive image from page 959 of The cyclopædia of anatomy and. The cyclopædia of anatomy and physiology cyclopdiaofana03todd Year: 1847 870 PACHYDERM ATA. these different operations are by no means equally in progress in all points of the tooth at the same time, but they occur much earlier in front than behind ; so that the anterior lamina; may be already consolidated by their summits and even by their bases while the bases of the middle ones remain separate, and when the posterior lamina are not even formed, or only represented by the patches of ivory that are first deposited upon the apices
Archive image from page 959 of The cyclopædia of anatomy and. The cyclopædia of anatomy and physiology cyclopdiaofana03todd Year: 1847 870 PACHYDERM ATA. these different operations are by no means equally in progress in all points of the tooth at the same time, but they occur much earlier in front than behind ; so that the anterior lamina; may be already consolidated by their summits and even by their bases while the bases of the middle ones remain separate, and when the posterior lamina are not even formed, or only represented by the patches of ivory that are first deposited upon the apices of the pulps. There was formerly much discussion as to the number of grinding teeth proper to the Elephant, and as early as 1715 the Royal Society of London observed that there is sometimes only one and sometimes two on each side in either jaw, and moreover that the first tooth is longer or shorter in proportion to the second in different individuals. Pallas first which is peculiar to the Elephant, viz. that its teeth diminish in length at the same time that they are worn away in depth. Whilst the exposed part of the tooth is thus worn away, that part of the root which corre- sponds with the portion ground down is re- moved by a very different process. When examined under these circumstances, the roots of the anterior denticles have the appearance of being eaten away as by a kind of caries, so that all the front of the tooth is thus removed when the grinding surface has ceased to be efficient, and the tooth, when about to be shed, is reduced to a very small size, however large it might have been originally. The tooth which is in use is therefore per- petually moving forward in consequence of this process, and making room for that which is in explained the real mode of the succession of progress of formation in the hinder part of the '' jaw to succeed it. This latter, in turn, by its development assists in pushing the first for- wards, so that it is strictly true that in the E
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