ORGANS OF SENSE. 147 
with a coarse towel or hair mitten. The deeper structure of the cuticle 
consists of softer scales or flattened cells, and the portion in immediate 
contact with the true skin is in an almost semi-fluid state, containing cells 
and nuclei. This fluid lymph or blastema contains numerous cell germs or 
eytoblasts, which gradually enlarge into cells which lie close together, and: 
cover every portion of the papillary surface of the cutis. As soon as the’ 
first layer is formed, a second is formed immediately beneath it, separating 
it from the true skin, and causing its drying and desquamation. The 
superficial scales adhere by their edges; the middle lamine of cells by their 
surfaces; the deep-seated are supported immediately by thin blastema. 
Granules of coloring matter are found distributed among the deeper cells. 
and in the connecting lymph, and it is upon the amount and tint.of these: 
that the complexion of the skin depends. In the Negro and other dark-' 
colored races, this coloring matter appears as a layer of pigment; it is not, 
however, a distinct or organized membrane, but merely coloring matter’ 
deposited in the interstices of the cells; as the latter approach the surface, 
any coloring matter they carry along with them is lost as they become dry: 
and hard, partly by evaporation, partly by undergoing some chemicak 
change. | 
The cuticle being itself insensible and unvascular, forms a most useful 
investment to the body, defending a highly sensitive surface from pressure: 
and friction, and from the stimulating effects of the atmosphere. It —— 
invaluable in resisting the evaporation of the fluids of the cutis. ; 
2. DERMIS, CHORION, OR Curis VERA. This is composed tassomrilsa by of: 
areolar tissue condensed into a firm, compact membrane, in which is inter- 
woven more or less of the yellow elastic fibrous tissue, with numerous: 
vessels and nerves. Its inferior surface is loose, open, and cellular, con- 
nected and continuous with the areolar tissue of the subjacent parts without: 
any very exact limitation or distinction; the subdermoid cellular tissue 
contains the cutaneous glands and hair bulbs, and the vascular and nervous 
ramifications which are to supply the dermis, as also more or less of adipose 
tissue. This subcutaneous adipose tissue or fat differs in different indivi- 
duals, according to age, sex, and constitution ; it is usually softer and more: 
abundant in the female, and at its maximum in the child. 
In the dermis, the upper portion, called the superficial or papillary 
lamina (although not a separate layer), presents a condensation of the 
areolar tissue into a smooth membranous surface which is exquisitely: 
yascular and sensible, and presents beneath the epidermis numerous minute’ 
elevated lines called papillz. This lamina is the seat of a vascular capil- 
lary plexus, and in the living body appears uniformly red when the cuticle 
has been detached. The papills are studded over this surfaee, varying in 
number and size in different parts of the body; the tactual sensibility of 
different parts of the body is in proportion to the abundance and size 
of these papille. Thus on the lower surface of the fingers the skin presents 
numerous curved or arched grooves and ridges; each ridge consists of ai 
row of conical papilla, and into the intervening grooves the epidermis sinks, 
and the small exhalant pores open. The exact structure of the papillz is 
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