518 PHILOSOPHICAL TRANSACTIONS. [ANNO 17 QQ. 



young and old elephants, and thence to draw some conclusions, respecting the pro- 

 gress of dentition in this useful animal. The first set of grinders, or milk teeth, 

 begin to cut the gum 8 or 10 days after birth; and the grinders of the upper jaw 

 appear before those of the lower one. Though this happens at first, yet in a few 

 months the grinders in the lower jaw come forward faster than those of the upper, 

 as I have observed in the heads of several elephants. In about 6 weeks, the first 

 set of grinders can be easily felt, consisting of 4 teeth, viz. one on each side of 

 either jaw; and as young elephants begin to eat grass, or some soft succulent food, 

 before they are 3 months old, we may conclude, that the first set of grinders* have 

 then completely cut the gum, and that dentition is not attended with any symptoms 

 of pain, or irritation, in the system. The milk grinders are not shed, as the tusks 

 are, but are gradually worn away, during the time the 2d set are coming forward; 

 and as soon as the body of the grinder is nearly worn away, the fangs begin to be 

 absorbed. 



I have not been able to ascertain the exact time when the 2d set of grinders make 

 their appearance, as I could never get an elephant to open his mouth in such a 

 manner as to permit me to examine his teeth accurately; but when the elephant is 

 about 2 years old, the 2d set are completely in use. At this period, the 3d set begin 

 to cut the gum. From the end of the 2d to the beginning of the 6th year, the 

 3d set come gradually forward, as the jaw lengthens, not only to fill up this addi- 

 tional space, but also to supply the place of the 2d set, which are, during the same 

 period, gradually worn away, and their fangs absorbed. From the beginning of 

 the 6th to the end of the gth year, the 4th set of grinders come forward, to sup- 

 ply the gradual waste of the 3d set. After this period, several other sets are pro- 

 duced. In what time these succeeding grinders come forward, in proportion to 

 their predecessors, I have not been able to ascertain ; but from the data already 

 given, I conclude, that every succeeding grinder takes at least a year more than its 

 predecessor to be completed; consequently, that the 5th, 6th, 7th, and 8th set of 

 grinders (a further succession I have not been able to trace) will take from 5 to 8 

 years, and probably much longer, each set, before the posterior lamina has cut the 

 gum. The milk grinders consist each of 4 teeth or laminae; the 2d set of grinders 

 of 8 or 9 laminae; the 3d set of 12 or 13; the 4th set of 15; and so on, to the 

 7th or 8th set, when each grinder consists of 22 or 23, which is the greatest 

 number I have observed. 



All these circumstances considered, I may venture to affirm, that the formation 

 of the teeth and mode of dentition, in the elephant, has but little analogy with 

 those of any other quadruped; nature having, by a peculiar and wonderful contriv- 

 ance, and in the most convenient manner, supplied this animal with a regular suc- 

 cession of teeth, till he attains a very advanced period of life. An advantage 

 which, as far as we know, no other quadruped possesses. The mode in which the 



* By a set, I mean 4, one grinder in each side of either jaw. — Orig. 



