OF LIVING ELEPHANTS. 201 



"weeks, and completely out at the end of three months. The second 

 are well out in two years. The third appear at this period, and cause 

 the second to fall on the sixth year ; they are in their turn pushed out 

 by the fourth in the ninth year. The following periods are not so 

 well known. 



In the two first elephants which I dissected, and in five dried heads, 

 which I examined, I constantly found three teeth at once, to wit, a 

 small molar tooth more or less ready to fall, a large one in its place, 

 and in full activitjr, and a germ more or less large, more or less con- 

 solidated, occupying all the bottom of the back jaw ; but in my last 

 elephant, which was about forty years old, there was not more than 

 two teeth, of which the second, which scarcely commenced to make its 

 exit from the alveolus, filled all the back jaw. 



We can easily judge by the depth of the detrition, whether a tooth 

 which is found isolated, was situated before or behind in the jaw r 

 those which were situated before never have any of their lamellae 

 entire. 



The number of the lacaellse which compose each tooth, goes on in- 

 creasing, so that each of them has more than the one which immediately 

 preceded it. 



M. Corse, who was the first to remark this, gives these numbers' 

 from his observations : the first have only four lamellee, the second 

 eight or nine ; the third twelve or thirteen, and so on to the seventh 

 or eighth, which have twenty-two or twenty-three of them. M. Corse 

 never saw teeth which had more than this. 



We are inclined to think, that these numbers are not very accU" 

 rate ; for we have a lower jaw, of which the first tooth has fourteen 

 lamellae, and the next fourteen germs of lamellae. M. Camper has 

 oneprecisely similar (Descript. Anat. d'un Elephant, p. 57,/?/. 19, Jig. 2).; 

 but in the upper jaw, which corresponded to ours, there is in the 

 active tooth thirteen lamellce, and in the germ of the one next it 

 eighteen. 



Independently of the number, there are differences with respect to 

 the thickness of the lamellae : they are thinner in the first teeth than 

 in the last: and as the jaws are shorter when they carry the first 

 teeth, it hapjjens that the number of the lamellae in activity is nearly 

 the same eve ry time, that is to say, from ten to twelve. 



When the elephant has grown, the space occupied by the lamellae' 

 in activity is, to be sure, greater ; but these lamellae are themselves 

 thicker, and al ways fill the space, whatever it be. 



As it requir es the same time to use the same number of lamellae, 

 the last teeth, which have much more of them, last much longer than . 

 the first. The replacements take place then at intervals, continually 

 lengthening, in proportion as the elephant advances in years. 



The elephant's'^ teeth, as those of all other animals, do not push out 

 their roots till t he body is perfect : the roots are formed by layers, 

 as the rest of th e tooth : the thing could not be otherwise. But why 

 this division in another direction, when the re-union of the cups 

 (calottes) of all t he gelatinous eminences seemed as if it should no 

 longer produce bu it one single body ? 

 To answer this question, which is one of general interest for all the 



