/ELIANS’ WART-HOG. 
223 
this subject towards the really two-fold type in 
the construction and the diversity in growth of 
the back teeth of the Wart Hog. We find, 
namely, the three anterior back teeth shaped and 
nourished in quite the same manner as all other 
teeth provided with enamel bodies and real roots. 
We farther must suppose a decay and dying 
away of the nourishing organ (bulbus) of these 
anterior back teeth, whenever they have obtained 
their full growth, (whether these animals expe- 
rience a change of teeth we cannot say, as none of 
the animals in our possession would justify us 
in asserting such a change,) and thus they are 
deprived of nourishment, which circumstance we 
would state as the cause why the alveola are then 
filling with a bony substance, and loosen, and 
finally push out the tooth they contained ; which 
tooth, in old age, is diminished to less than half 
its size, in consequence of the drain sustained by 
its solid organ of nourishment. The three 
anterior back teeth are thus, by the nature of their 
construction and functions, as much subject to 
decay and falling out as the teeth of all other 
animals advanced in age. It is altogether different 
with respect to the fourth, the largest and hindmost 
of the back teeth. The latter is, as Fred. Cuvier 
observed, a compound tooth,* ( dent composee,) and 
* S. des Dents des Mammiferes, Disc, praeliiu. p. xlvi. 
