THE KIDNEYS AND SKIN. 



443 



cutis vera which is turned into leather, its white fibrous tissue 

 forming an insoluble and tough compound with the tannin 

 of the oak-bark employed. Wherever there are hairs, bun- 

 dles of plain muscular tissue are found in the corium ; it 

 contains also a close capillary network and numerous lym- 

 phatics and nerves. In shaving, so long as the razor keeps 

 in the epidermis there is no bleeding; but a deeper cut shows 

 at once the vascularity of the true skin. 



The outer surface of the corium is almost everywhere 

 raised into minute elevations, called the papilla, on which 



a 



h 

 m 



f 



so 



FIG. 186. A section through the skin and subcutaneous areolar tissue, ft, 

 horny stratum, and m, deeper more opaque layer of the epidermis ; d, dermis; 

 passing below into sc, loose areolar tissue, with fat, /, in its meshes : above, dermic 

 papillae are seen, projecting into the epidermis which is moulded on them, a, 

 opening of a sweat-gland ; gl, the <rland itself. 



the epidermis is moulded, so that its deep side presents pits 

 corresponding to the projections of the dermis. In Fig. 135 

 is shown a papilla of the corium containing a knot of. blood- 

 vessels, supplied by the small artery, f, and having the blood 

 carried off from them by the two little veins, g g. Other 

 papillae contain no capillary loops but special organs connected 

 with nerve-fibres, and supposed to be concerned in the sense 



