SWEAT-GLANDS. 



227 



microscope, is found to consist of a fine tube, coiled up into a ball 

 (though sometimes forming an irregular or flattened figure) ; from ^Yhich 

 the tube is continued, as the duet of the gland, upwards through the 



Fig. 155. 



Fi-. 156. 



i»----^ 



--C 



/■ 



/- 



Fig. 155. —Vertical Section of the Skin and Subcutaneous Tissue, from end of 

 THE Thumb, across the Ridges and Furrows, magnified 20 Diameters (Ki311iker). 



«, horny, and h, mucous layer of the epidermis ; r, cerium ; d, pannicidus adiposus ; 

 e, papilliB on the ridges ; /, fat-clusters ; ff, sweat-glands ; /(, sweat-ducts ; i, their 

 openings on the surface. 



Fig. 156. — Magnified View of a Sweat-Gland, with its Duct (Wagner). 



«, the gland surrounded by fat-cells ; b, the duct passing through the corium ; c, its 

 continuation through tlie lower, and d, througli the upper part of tlie epidermis. 



true skin and cuticle, and opens on the surface by a slightly widened 

 orifice. Qlie duct, as it passes through the epidermis, is twisted like a 

 corkscrew, that is, in parts where the epidermis is sufficiently thick to 

 give room for this ; lower down it is but slightly curved. Sometimes 

 the duct is formed of two coiled-np branches which join at a short 

 distance from the gland, as happens to be the case in the specimen repre- 

 sented in fig. 156. The tube, both in the gland and where it forms 

 the excretory duct, consists of an investment of connective tissue, con- 

 tinuous with the corium, and reaching no higher than the surface of 

 the true skin, a thin membrana propria and an epithelial lining, con- 

 sisting of one or more strata of cells (often containing brownish 

 pigment), and continuous with the epidermis, which alone forms the 

 twisted part of the duct. The larger gland-ducts in the axilla, at 

 the root of the penis, on the labia majora, and in the neighbour- 

 liood of the anus, contain between their coats a layer of non-striated 



Q 2 



