280 ELEMENTS OF HISTOLOGY. [Chap, xxxiv. 



the liairs of the axilla and pubic region, those of 

 the male whiskers and moustache, are coarse and 

 thick, while the hairs of other places e.g., the skin- 

 surface of the eyelids, the middle of the arm and 

 forearm, &c. are very minute : but, as regards struc- 

 ture, they are all very much alike. 



379. A complete hair and hair-follicle that is, the 

 papillary hair of Unna shows the following struc- 

 ture : 



The hair-follicle. Each hair-follicle commences 

 on the free surface of the skin with a funnel- 

 shaped opening or mouth; it passes in an oblique 

 direction through the corium into the subcutaneous 

 tissue, in whose middle strata i.e., in the stratum 

 adiposum it terminates with a slightly enlarged 

 extremity, with which it is invaginated over a rela- 

 tively small fungus-shaped papilla. This latter is of 

 fibrous tissue, containing numerous cells and a loop of 

 capillary blood-vessels. 



Minute hairs do not reach with their follicles to 

 such a depth as the large coarse hairs, the former not 

 extending generally much farther than the deep part 

 of the corium. Degenerating and imperfect hairs 

 (see below) also do not reach to such a depth as the 

 perfect large hair-follicles. In individuals with 

 " woolly " hair e.g., the negro race (0. Stewart), and 

 in animals with " woolly " hair, siich as the fleece of 

 sheep the deep extremity of the hair-follicle is 

 curved, sometimes even slightly upwards. 



380. The structure of a hair-follicle is as follows 

 (Fig. 148) : There is an outer coat composed of 

 fibrous tissue; this is the fibrous coat of the Jiair- 

 sac. It is merely a condensation of the surround- 

 ing fibrous tissue, and is continuous with the 

 papilla at the extremity of the hair-follicle. About 

 the end of the hair-follicle, or sometimes as much 

 as in the lower fourth, there is inside of this 



