356 SPECIAL PHYSIOLOGY. 



adherent to the subjacent parts generally, becoming blended with the 

 subcutaneous areolar and fatty tissue, the fasciae, and even with the 

 cutaneous muscles. 



The cutis is made up of interlacing bundles of white areolar tissue, 

 mixed with yellow elastic fibres. Immediately beneath the rete mu- 

 cosum, its structure is almost homogeneous, presenting a compact, 

 scarcely fibrillated appearance. Somewhat deeper, bundles of fine 

 fibres, with small areolae, appear. In the deepest layers, the fibres are 

 large and coarse ; the dense areolar network is here loose, and open- 

 ing out, incloses the hair follicles with their sebaceous glands, and 

 small masses of fat. In most situations, scattered contractile fibre- 

 cells, or plain muscular fibres are found, mixed up with the fibrous 

 and elastic tissues; they are always present where hairs exist, to 

 which parts they are often attached; on the palms and soles, where 

 these are absent, no muscular fibres are ever seen. The cutis, in 

 some parts of the body, as in the palms and soles, is closely adherent 

 to the fascia beneath it; in the face, it gives attachment, by its under 

 surface, to many of the fibres of the muscles of the eyebrows and 

 mouth. The skin is very loosely attached over the angles of the 

 joints, where, moreover, the so-called subcutaneous bursce are found ; 

 these are closed sacs, situated between the integument and the promi- 

 nences of the bones, by means of which the movements of the parts 

 are facilitated. The thickness of the cutis varies in different parts of 

 the body; it is thickest in the sole, and thinnest in the eyelids, being, 

 in the former situation, about a line and a half thick, and in the latter, 

 less than a quarter of a line ; as a rule, it is thicker in the male than 

 in the female. The thickness of the entire skin is determined by the 

 cutis, except in the palms and soles, where the cuticle is disproportion- 

 ately thick. 



The surface of the cutis, as seen when it is denuded, is covered, in 

 many places, with little conical-shaped projections, called papillce^ Fig. 

 66, 4. These are prolongations of the upper compact tissue of the 

 cutis into the rete mucosum of the cuticle, from the depressions in 

 which, already mentioned, they can be drawn out, in macerated speci- 

 mens, after death. The papillae are best seen on the palms of the 

 hand, where they are largest and most numerous; they are usually 

 arranged in double rows upon the cutaneous ridges (Figs. 65, 66), and 

 are generally divided, so as to form compound papillae, 67, a. In the 

 palm, the number of simple papillae on a Paris square line ranges from 

 150 to 200 ; upwards of 80 compound papillae have been counted on 

 the same space. (E. Weber.) On the free border of the lips they 

 are also very numerous, but they do not present any regular arrange- 

 ment. The cutaneous papillae on the fingers and palm measure from 

 y^ffth to jJsth of an inch in length; in the soles, they are nearly as 

 large, but in other situations, where there is less tactile sensibility, 

 they are few in number, short, small, and scattered, measuring from 

 7 {0th to T^Gffth of an inch in length; on some parts of the body, the 

 papillae become indistinct, or are even altogether absent. 



The cutis is abundantly supplied with bloodvessels, lymphatics, and 

 nerves. Its general surface is covered with a close capillary network, 



