different Species of Asiatic Elephants. 215 
across the tooth, surrounding the central part on which it was 
formed, and taking the irregular indented plaited shape of the 
lamellae. (Tab. VI. Fig. 2.) This bony centre, on which the 
enamel is formed, is harder than the matter which joins 
the teeth together, does not wear so fast, and consequently re- 
mains higher. Tab. VII. IX. and X. show these processes very 
distinctly. 
The number of teeth of which a grinder is composed, varies 
from four to twenty-three, according as the elephant adr- 
vances in years; so that a grinder or case of teeth, in full 
grown elephants, is more than sufficient to fill one side of the 
mouth ; (Tab. X. and XI.) in proportion, however, as the fore- 
most layers are worn away, the succeeding ones come forward, 
to supply their places. 
The denticuli of which each layer or tooth is composed, are 
much larger, and fewer in number, in old than in young ele- 
phants; (Tab. VI. Fig. 1 and 2. also Tab. VII. VIII. IX. X. 
and XL) in consequence of this, the same number of laminae 
generally fills the jaw of a young or of an old elephant ; and, 
from three till fifty years, there are from ten to twelve teeth or 
laminae in use, in each side of either jaw, for the mastication of 
the food. (Tab. VII. X. and XI.) 
When several of the anterior teeth of which a grinder is 
composed have been completely formed, and each tooth co- 
vered with its proper enamel, they become firmly united 
(beginning at the fore part) by the intervention of the com- 
mon bony matter, which gradually fills up the interstices be- 
tween them. 
When the bodies of several of the anterior laminae have been 
connected together, the inferior edge of each becomes united, in 
Ff 2 
