SPECIAL HISTOLOGY. 



OF THE EXTERNAL INTEGUMENT. 



-Of the Skin Proper. 



A. CUTIS. 



Fig. 31. 



§ 33. The external shin (fig. 31) consists essentially of an in- 

 ternal layer, composed principally of connective tissue, and abun- 

 dant in vessels and nerves, the true skin, cutis, derma (fig. 31, c. d.) : 



and of an external covering made 

 up of cells only, the epidermis (fig. 

 31, a. b.) ; and, in addition, many 

 peculiar glandular and horny organs 

 appertain to it. 



The cutis or derma may again be 

 subdivided into two layers : the 

 subcutaneous cellular tissue, tela 

 cellidosa subcutanea, and the corium 

 proper (fig: 31, c); the latter of 

 which, from its richness in vessels 

 and nerves, constitutes the most 

 important part of the external 

 integument. 



§ 34. The subcutaneous cellular 

 tissue (tela cellidosa subcutanea) is 

 a moderately compact membrane, 

 formed chiefly of connective tissue, 

 which, in most parts of the body, 

 incloses within its meshes a con- 

 siderable quantity of fat-cells (fig. 

 31,/.), and thus appears as a fatty 

 layer {panniculus adiposus), of va- 

 riable thickness. In some localities, 

 however, e. <j., in the ear, eyelids, scrotum, penis, and nymphee, it 



Vertical section through the skin of the 

 hall of the thumb, transversely through two 

 ridges of the cutis; magnified 20 times, a. 

 Horny layer of epidermis ; 6. its mucous 

 layer ; c. corium ; d. panniculus adiposus 

 (upper parts) ; e. papillae of the cutis ; /. fat 

 globules; g. sudoriparous glands; h. their 

 canals ; i. sweat-pores. 



