GLANDS OF THE SKIN. 



325 



SWEAT GLANDS. 



The glandulae sudoriparae are long unbranched tubes termina- 

 ting in a simple coil (described by Oliver Wendell Holmes as resembling a 

 fairy's intestine, Fig. 378). The coil is found in the deep part of the corium 

 or in the subcutaneous tissue (Fig. 359). The duct pursues a straight 

 or somewhat tortuous course to the epidermis 

 which it enters between the connective tissue 

 papillae. Within the epidermis its spiral wind- 

 ings are pronounced; it ends in a pore which may 

 be detected macroscopically. 



The epithelium of the ducts consists of two or 

 three layers of cuboidal cells; it has an inner cu- 

 ticula, and an outer basement membrane covered 

 by longitudinal connective tissue fibers. With- 

 in the epidermis its walls are made of cells of 

 the strata through which it passes. The secre- 

 tory portion of the gland (3.0 mm. long according to Huber) forms about 

 three-fourths of the coil, the duct constituting the remainder. The secretory 

 epithelium is a simple layer of cells, varying from low cuboidal to columnar 

 according to the amount of secretion which they contain. Those filled 

 with secretion present granules, some of which are pigment and fat. The 

 product is eliminated through intra- and intercellular secretory capillaries. 



FIG. 378. MODEL OP THE 

 COILED PART OF A SWEAT 

 GLAND PROM THE SOLE OP 

 THE FOOT. (After Huber.) 



Membrana propria. 



Cuticula. 



A. Duct in 

 cross section. 



Nuclei of Muscle D. Low epithelium from 

 gland cells, fibers. a coiled tubule. 



Membrana propria. 



Muscle fibers. 



K Muscle nucleus. 

 Cuticula. 



Muscle fibers, j 



B. Columnar epithelium 

 from the coiled tubule. 



Membrana propria. 

 - Muscle fiber. 



C. Surface view 

 of the coiled tubule. 



E. Cross section of 

 coiled tubule. 



FIG. 379. A-D, PROM A SECTION OF THE SKIN OP THE AXILLA; E, PROM THE FINGER TIP OF A MAN 

 OF 23 YEARS. X 230. E is not a true cross section. 



It is ordinarily a fatty fluid for oiling the skin, but it becomes the watery 

 sweat under the influence of the nerves. The gland cells are not destroyed 

 by either form of activity. The secretory tubule is surrounded by a 

 distinct basement membrane, within which there is a row of small longi- 

 tudinally elongated cells described as muscle fibers. They do not form 



