STRUCTURE OF THK SKIX. 81 



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 common 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 in its nature according to the functions 

 of the organ which it is destined to protect. It is destitute 

 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 ine- 

 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 



