As each tooth advances, only a small portion pierces the gum at once; one of twelve or fourteen _laminae_, for instance, shows only two or three of these through the gum, the remainder being as yet imbedded in the jaw; and in fact the _tooth is complete at its fore part_, where it is required for mastication, _while behind it is still very incomplete_; the laminae are successively perfected as they advance. The molar of an Elephant _can never, therefore, be seen in a perfect state_: for if it is not worn in front, the back part is not fully formed and is without fangs; and when the structure of the hinder portion is perfected, _the front part is already gone_. "When the complex molar cuts the gum, the cement is first rubbed off the digital summits; then their enamel cap is worn away, and the central dentine comes into play with a prominent enamel ring; the digital processes are next ground down to their common uniting base, and a transverse tract of dentine, with its wavy border of enamel, is exposed; finally, the transverse plates themselves are abraded to their common base of dentine, and a smooth and polished tract of that substance is produced. From this basis the roots of the molar are developed, and increase in length, to keep the worn crown on the grinding level, until the reproductive force is exhausted. When the whole extent of a grinder has thus successively come into play, its last part is reduced to a long fang supporting a smooth and polished field of dentine, with sometimes a few remnants of the bottom of the enamel folds at its hinder part. Then, having become useless, it is attacked by the absorbent action, by which, and the pressure of the succeeding tooth, it is finally shed."[86] With these physiological facts ascertained, let us proceed to the determination of the actual age of our noble Dauntelah. The molar in present use has a length of about nine inches, and a diameter of three and a half. Its crown is crossed by about eighteen enamel-plates; of which the anterior ones are much worn away, while the hinder ones can scarcely be counted with precision, as they have not wholly cut their way through the gum. These characters indicate the fifth molar (or set of molars) of the whole life-series. And the following facts will help us now to fix the actual age, at least approximately.