RHINOCEROS. 
159 
to me to be an anomaly very deserving examina- 
tion. Dispersed over the skin of all animals are 
pores, which I have supposed secrete a peculiar 
fluid, which may be designated by the name of 
corneous matter. This secretion or fluid is 
designed by nature for the forming of various 
most useful and important additamentae, all of 
which continue growing during the whole life, 
have an insertion not deeper than the skin, and 
are farther distinguished by the absence of all 
sensibility and vascular organization, being purely 
exuvial parts, like the perfected feathers of birds. 
In all these parts, the growth takes place by the 
addition of more matter at their base. When 
these pores are separate, they produce hairs ; 
when they are confluent, and in a line, they pro- 
duce the nails, the claws, and the hoofs, the fibrous 
appearance of which naturally leads to the suppo- 
sition of their being confluent hairs ; and the same 
may be said of the scales of the Manis, the quills 
of the Porcupine, Hedge-hog, and other animals, 
which may be regarded as hairs of extraordinary 
size. When the pores are confluent, and in a 
ring, they furnish the corneous core of the horns 
of the animals of the ruminating class ; and when 
confluent on a circular order, they supply matter 
for the formation of a solid horn, such as we see 
in the Rhinoceros. At its base, it is, in most 
instances, evidently rough and fibrous, like a 
