THE SKIN AND ITS APPENDAGES. 



193 



THE ORGANS OF SENSE. 

 THE SKIN AND ITS APPENDAGES. 

 Name the Divisions of the Skin. It is divided into the 

 ( Superficial Epithelial layers. 



Epidermis, or Cuticle, 





me iiuc OKIII. 



Mucosum , the p i gm entary layers. 

 Papillary Layerf next below the rete, from which 

 it is separated by a homogeneous basement 

 membrane. 

 ^ Corium,d the deepest portion. 



What Structures lie in and beneath the Skin ? The 

 Sensitive Papilla, containing the Tactile Corpttscles in very sensitive parts, 

 in the papillary layer of the Derma. 



Sweat-glands. />& Hair-roots. h^\ , , 



-;-.., V In the Sub- cutaneous Cellular Tissue. 

 Sebaceous G/anas.* rat Lells. e ) 



Ducts of the Sweat-glands. 



Hair-follicles, into which most of the seba- 



ceous ducts open. 

 Ducts of the Sebaceous Glands, occasionally. 



Describe the Structure of the Epidermis. It is an unorganized epithe- 

 lial structure, having no vessels or nerves. The cells of which it is composed 

 are agglutinated together in a lami- 

 nated arrangement, 'are flat and dry 

 on the surface, round and softer in the 

 central portion, columnar and softest 

 in the deepest layers. The lowest 

 and softest layers are named the 

 Rete Mucosum, which is closely 



moulded upon the papillary layer 



of the derma, and contains pig- 



ment cells, to which the color of 



the skin is due. 



Describe the Structure of the 

 Derma. The true skin is a highly 

 organized, tough yet elastic tissue, and 

 serves to protect the parts beneath, to 

 perform the functions of excretion and 

 absorption, and as the chief seat of the 

 sense of touch. It consists of fibro-areo- 

 lar tissue, vessels and nerves. The 



Perforate both the Derma 

 and the Epidermis. 



FIG. 96. 



