542 .ESTHESTOLOGY. 



the pigment exists which gives colour to the skin. The deep 

 surface of the epidermis is accurately moulded on the papillary 

 layer of the true skin, and, when removed by maceration, 

 presents depressions, which correspond to the elevations on the 

 dermis; from the cuticle, tubular prolongations pass into the 

 sebaceous and sudoriferous glands. The outer surface is marked 

 by a network of furrows, the deep ones forming lozenge-shaped 

 spaces. 



The DERMIS, or true skin, is vascular and highly sensitive, 

 being the seat of touch. It is attached to the underlying parts 

 by a layer of areolar tissue, which usually contains fat, hence 

 called the panniculus adiposus. The dermis consists of fibro- 

 areolar tissue and vessels of supply ; it is divided into two layers, 

 the deep or true corium, and the upper or papillary. The 

 deep corium consists of strong interlacing fibrous bands, chiefly 

 white ; its meshes are larger, and more open towards the attached 

 surface, giving lodgment to the sweat-glands and fat. The 

 papillary or superficial layer is formed of a series of small conical 

 eminences or papillae, which are highly sensitive, and consist of a 

 homogeneous transparent tissue. The blood-vessels form dense 

 capillary plexuses in the corium, terminating by loops in the 

 papillae. The papillary nerves run in an undulating manner, 

 usually terminating in loops. 



GLANDS OF THE SKIN. 



These are the sebaceous and sudoriferous. 



The SEBACEOUS GLANDS, lodged in the corium, are most 

 abundant in parts exposed to friction. They generally open into 

 the hair follicles, and occasionally on the surface of the skin. 

 Each gland consists of a small duct, Avhich terminates in a 

 lobulated recess. These lobules vary, and are, as is the duct, 

 lined with epithelium. They are filled with sebaceous matter, 

 which, as it is secreted, is discharged into the hair sacs. 



The SUDORIFEROUS or sweat glands are situated in the sub- 

 cutaneous areoiar tissue, surrounded by a quantity of fat. They 

 are small, round, reddish bodies, each of which consists of one or 

 more fine tubes coiled into a ball, the free end of the tube being 

 continued up through the true skin and cuticle, and opening on 

 the surface by a funnel-shaped orifice. Sometimes there are two 

 apparent ducts, which unite at a short distance from the gland. 



