The encasement of our body, the skin, which serves as a protecting envelope to the deeper structures, is continually shedding its most superficial layer. The normal desquamation of dried horny cells is a physiologic occurrence which takes place almost unobserved and imperceptibly. This uppermost stratum of the epidermis, made up of ever-detaching horny cells, is called the horny layer. It is this layer which gives the surface of our body its armor plate, as it were. On the good condition of this surface protection depends the intactness of our skin and its ability to resist microbic and mechanical influences.
A normal and healthy cornification which the constantly renewing deeper layers undergo as they emerge to the surface from the state of succulency below to that of desiccation and cornification above keeps the skin intact in its continuity. The existence of fat in the cells of the stratum lucidum and from
WEISS L. PARAKERATOSIS OSTRACEA (SCUTULARIS). JAMA. 1912;LIX(5):343-346. doi:10.1001/jama.1912.04270080025008