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enamel is disposed. This occurs most particularly in a space in the 
anterior part of the surface. Here one deeply undulating line of 
enamel forms the parietes of one wide and deeply indented compages 
of osseous matter, occupying, as may be seen by the figure, the space 
of four or five plates. It is very evident that this tooth could not, upon 
the decomposition of the crusta petrosa taking place, divide, in this 
part, into detached flat plates, as in the teeth of the recent and of the 
common species of fossil elephants. This structure is also observable 
in the fossil tooth from Wellsbourn, which has been already noticed. 
This extraordinary structure also exists in the curious and interesting 
specimen, Plate XX. Fig. *]. This tooth, with the locality of which I 
am unacquainted, having purchased it at the sale of Mr. Forster’s col- 
lection, is one, which must have been on the point of being excluded 
from its alveolus ; the plates on its fore part being entirely worn away, 
and, of those on the posterior part, some very shallow portions only 
remaining. These, however, are sufficient to show, that the plates 
in this tooth were formed and arranged in a similar mode with those 
of the preceding tooth. 
In the fore part of this tooth, from which the plates have been re- 
moved, is a very smooth and polished surface of a thin coat of the 
crusta petrosa. This is, indeed, so thin, that at the root of the small 
projecting piece of enamel, in nearly the middle of the tooth, a small 
part is discoverable, where the crusta petrosa itself is worn through, 
and a portion of the substance of the root itself has been acted upon. 
Behind this, are two detached bands, linearly and transversely disposed. 
Just above the upper part of one of these commences a line of enamel, 
which proceeds in undulations for the space of two plates, through half 
the width of the surface, the remaining half being filled up by two 
separate terminations. The line of enamel then passes on, by deep un- 
dulations, to the back part of the tooth, filling up the space of three 
more plates. This peculiarityof structure will however be better under- 
stood from the figure, than it canbe fromeventhemost exact description. 
