STRUCTURE OF THE SWEAT GLANDS. 239 



necessarily perforate the entire thickness of the corium as 

 well as the mucous and epidermal layers. It either runs 

 straight or with only a slightly sinuous course through the 

 corium, and always enters the thick mucous layer between the 

 papillae, traversing this in a spiral manner. 



Fig. 200. Glomemli of Sudoriparous gland, divided in various 

 directions, a, Sheath of the gland ; 6, enchyma cells ; c, gland tube ; 

 d, divided bloodvessel ; /, loose connective tissue, forming a capsule 

 to the gland. 



As the cubic cells of the rete mucosum become converted 

 into the flat scales of the epidermis, the excretory duct must 

 present a greater number of coils in proportion to the thickness 

 of the latter ; where the epidermis is thin, the tube scarcely 

 forms a semispiral; where it is thick, however, there may be 

 as many as twenty, which on both sides of the body turn in 

 corkscrew fashion to the right (Welcker). In a few regions, 

 as on the hands and feet, the external opening is funnel-shaped 

 and is visible even to the unaided eye as the sweat pores. In 

 these parts the apertures are situated at regular distances from 

 each other in the furrows between the striae, but elsewhere they 

 usually open in groups (Krause). None are found upon the 

 prepuce or glans penis. 



From the level of the rete mucosum, outwards, the excretory 

 duct has no special wall, but is bounded in the rete mucosum 

 itself by concentrically arranged concavo-convex cells, and in 

 the epidermis by the scales of which it is composed. 



In the corium the duct is formed by a tap -shaped process 



