STRUCTURE OF THE SKIN. Sf 
the cuticle, —the corpus mucosum,—the corium,—the pan- 
niculus carnosus,—and the cellular web. 
1. The Cuticle— This is likewise termed Epidermis, or 
Scarf-skin, and appears to be commen to all animals. It 
constitutes the exterior layer of the skin, and covers not only 
those parts which are exposed to the influence of the at- 
mosphere, or the waters, but the different openings of the ex- 
tremities of the vessels, and lines the central surface of these 
with a coating, varying inits nature according to the functions 
of the organ which it is destined to protect. It is desiitute 
of bloodvessels, nerves, and fibres, and usually consists of thin 
transparent membrane, possessing little tenacity. Various 
pores may be observed on its surface, which are the mouths 
of the vessels of the inner layers of the skin; and it is va- 
riously marked by grooves or ridges, depending on the me- 
qualities of the surface which it covers. 
It resists putrefaction for a great length of time; and 
may easily be obtained in a separate state from the other 
members, by maceration in water. It likewise separates 
from the inferior layers, and becomes very obvious in the 
case of blisters. Alcohol loosens its connection with the 
inner layers very readily, in many of the inferior animals, 
such as the earth-worm. So far as it has hitherto been sub- 
jected to chemical experiment, it appears to consist of co- 
agulated albumen. 
The cuticle exists before birth; and may be observed 
thickest on those places destined to be exposed to the great- 
est friction; such as the palms of the hands and the soles 
of the feet. After birth, it is speedily renewed on parts 
which have been wounded, or increased in thickness in those 
places which are frequently subjected to pressure. It is 
almost constantly undergoing changes. It exfoliates in the 
form of scales, from our own heads and from the skin of 
VOL. I. F 
