104 . GLANDS. 



come obliterated, their secretion, accumulating within, 

 distends them and alters their shape, so that they 

 become spherical, and thus form what are known as 

 the Ovula Nabothi. 



sweat glands. Sudoriparous Glands. These tubular glands oc- 

 cupy the deepest layers of the skin (PL XXIII. fig. 

 I. 8). The body of the gland, or glomerula, is a little 

 spheroidal mass, or ball, averaging one-fourth of a line in 

 diameter. It consists of a tube, rolled and twisted upon 

 itself, and terminating by a blind extremity, which, 

 in rare cases, is bifurcated (PL XIX. fig. IV). Its 

 walls are formed by an extremely thin and structure- 

 less basement membrane (reVo-th to TaV^th of a line in 

 diameter), which is strengthened externally by some 

 fibres of connecting tissue very rich in plasmatic cells 

 (fig. IV. 4), and which may be regarded as consti- 

 tuting the fibrous envelope of the gland. The inter- 

 nal surface of the tube is lined by a single layer of 

 pavement epithelium, whose cells measure 4<roth of a 

 line in thickness (fig. VI. 2). Finally, the glomerula 

 is surrounded by a rich vascular network, which 

 affords the materials for its secretion. Of the mode 

 of innervation of these glands we are as yet ignorant. 

 The excretory duct of a sweat gland, after leaving the 

 glomerula, runs directly outwards through the sub- 

 stance of the skin, towards the bottom of one of the 

 furrows upon its surface, and then, traversing the 

 epidermis, terminates by an oblique opening upon its 

 outer surface. During its course through the skin 

 proper it is perfectly straight ; but, in traversing the 

 epidermis, it turns upon itself, forming a close spiral 

 twist (PL XXIII. fig. I. 9). In the epidermis the 



