different Species of Asiatic Elephants. 233 
layers must be completely worn away, before the posterior 
teeth can cut the gum. 
Above the last layer of this grinder, there appears an inci- 
pient alveolus for another succeeding grinder ; though the ele- 
phant to which this head belonged appeared aged. 
AAA. The line of separation between the alveolus and bones 
of the upper jaw. 
BBB. The surface of the tooth to which the gum is at- 
tached. 
C. An incipient alveolus for a succeeding grinder. 
Tab. XI. 
Represents, in situ, a very complete grinder, about half the 
natural size, in the right side of the lower jaw of a full grown 
elephant. It consists of twenty-two layers or teeth, and the 
three farthest back are not yet attached to their anterior laminae. 
Here the gradual progress of ossification in the fangs is distinctly 
seen ; and, from the apex of the alveolus, to near the centre of 
the grinder, it is not attached to the jaw. A small portion of 
the jaw bone, covering the large foramen through which the 
apex ascends, has not been removed. In this, as well as in the 
last plate, the grinder completely fills the jaw, and only half of 
the grinder is employed for masticating the food. The anterior 
teeth appear evidently to rise by the addition of the fangs; 
which here, as well as in the grinders of the upper jaw, 
lengthen as the teeth wear away, till, the roots being completed, 
they begin to be absorbed. The anterior fangs are very dis- 
tinct, but still hollow at the points. The bony lamella ap- 
pears extending backwards, as the foundation of the succeeding 
roots. 
