236 SKIN, HAIR, AND NAILS, BY ALFRED BIESIADECKI. 



bans has also seen in the higher layers of the rete a consider- 

 able number of dark-violet bodies, from each of which a single 

 process is directed downwards, whilst several run towards the 

 stratum corneum. The former he believes to be continuous 

 with the more deeply seated nerve-fibres. 



SEBACEOUS FOLLICLES. 



The sebaceous follicles (glandulce sebiferce), also named on 

 account of their connection with the hairs, glands of the hair 

 follicles, are simple or compound acinous glands, the excretory 

 duct of which rarely opens immediately upon the surface, but, 

 as a rule, into the hair follicle. In the case of the larger hairs 

 they appear to be appendages of the follicle, whilst in pubescent 

 hairs the relation is reversed, the small hair follicles appearing 

 to open into the wide excretory duct of the gland. They are 

 always situated in the corium, and never reach into the subcu- 

 taneous connective tissue. 



The sebaceous follicles consist of gland substance and an ex- 

 cretory duct. The former is composed of gland lobules (Acini) 

 or sacculi, of pyriform shape, filled with enchymatous cells, of 

 which from two to twenty open into each excretory duct. The 

 gland lobules thus consist of a gland sac (sheath) and enchyma 

 cells. 



The gland sac is composed of a transparent and colourless 

 nucleated membrane that is apparently destitute of structure, 

 but when treated with solution of silver exhibits groups of 

 cells ; externally it is bounded by a dense layer of connective 

 tissue, with elastic fibres, which is traversed by a moderately 

 cloze vascular plexus. The sebaceous follicles are not known 

 to possess any special supply of either lymphatics or nerves. 



The enchyma cells that fill up the whole of the interior of 

 the saccule, with the exception of a small central cavity, con- 

 sist of epithelial cells, of which the most external, that lie in 

 contact with the gland sac, resemble the deeper cells of the 

 mucous layer, except only that the nucleus is more distinctly 

 visible. Those that are situated more internally first become 

 filled with small fat molecules, and then with larger fat drops 

 that surround and conceal the nucleus, and cause the cells to 

 increase in size. After the fat has been extracted, round spaces 



