THE CUTIS. 355 



fluid between it and the vascular cutis, forms the blebs or bullse seen 

 in certain skin diseases, and after burns, scalds, or the application of 

 blisters. On separating the cuticle from the cutis, after death, when 

 some decomposition has taken place, the under surface of the former 

 is found to be accurately moulded to the upper surface of the cutis, 

 closely following all the flexures, markings, and ridges of the skin, 

 which are really formed in the cutis ; it further presents numerous 

 small pits or depressions, which receive the conical projections of the 

 cutaneous papillae. A prolongation of the cuticle lines the sides of 

 the hair follicles, and the glands of the skin. 



In the palms and soles, where the entire skin is thickest, the cuticle 

 measures about J^th of an inch ; in other parts, where the skin is very 

 thin, it is not more than 2 \Q^\\ of an inch in thickness. In the palms 

 and soles, it grows thicker, from the effects of hard work and pres- 

 sure. The greater thickness of the whole skin, in some situations, as 

 in the hands and feet, cannot, however, be solely attributed to the 

 effects of external influences, for the skin of these parts is thickest, 

 even in the new-born infant. During life, the cuticle is constantly 



Fig. 66. 



Fig. 66. Vertical section of a portion of the skin of the finger, made across three of the curved ridges, 

 shown in Fig. 65, magnified about 20 diameters; 1. section of the dry part of the epidermis. 2. Section of 

 the soft, mucous, or Malpighian rete mucosum, the chief seat of the coloring matter in the dark races. 3. 

 Section of the cutis or derma, gradually becoming more areolar, until it joins the subcutaneous areolar 

 adipose tissue. 4. Elevations of the upper compact portion of the cutis. named the papilla;, placed in rows 

 across the ridges just mentioned. 5. Coiled tubuli of the sudoriferous, or sweat glands, lying near or in 

 the areolar subcutaneous tissue. 6. Long duct of one of these glands, forming a waved line through the 

 cutis, 3, but passing spirally, like a corkscrew, through the cuticle, l,and then opening on the surface of 

 a ridge. 7. Small masses of the subcutaneous fat. (Kolliker.) 



undergoing loss, by the process known as desquamation, which con- 

 sists of a throwing off of the superficial epidermoid scales. But these 

 are constantly being renewed by fresh epidermoid cells, originating on 

 the surface of the true skin, and gradually undergoing transforma- 

 tion, from the spherical to the flattened shape, as they approach the 

 surface of the cuticle. 



The cutis, or true skin, also called the corium and derma, Figs. 66, 

 67, 3, covered everywhere by the 1 cuticle, is a dense, moist, tough, 

 and flexible fibro-areolar membrane, of a pinkish-white color. It is 



