THE HAIR. 85 



follicle. These muscles were all of the striped kind, but 

 extremely soft and extensile, and among the fibres were a 

 number of very elongated nuclei, but I saw no distinct evi- 

 dence of the admixture of unstriped muscle." 



Development of Hair. At the spot where a hair is to 

 develop, a thickening is noticed. Here the epithelial cells 

 accumulate in large numbers, and press dn the hypertrophied 

 portion of vascular skin which is to be the papilla. By the 

 progressive accumulation of the cells, a deep recess is formed, 

 which becomes the hair-follicle. From the vascular papilla, 

 by this time fully formed, material is thrown out by which 

 the cells are enabled to multiply, and, being pressed up in 

 the follicle, find their way at last through the superficial 

 layer of cuticle beneath which cells first began to accu- 

 mulate. Thus the hair breaks its way through the solid 

 epidermis, and is, as Virchow would express himself, the 

 result of the proliferation of the deeper cells ; or, in Dr 

 Beale's phraseology, may be described as 'formed material' 

 advancing, and in different stages of change, from the ' ger- 

 minal matter ' near the vascular papilla, to the corneous cor- 

 tical layer and point. 



In some animals, and especially in the domestic sheep, 

 the hair is of singular fineness, and acquires properties well 

 known to belong to it as wool. Sheep in a wild state have 

 much hair, mixed with the wool, on their bodies, and it is 

 only by careful management in breeding that the kemps or 

 hairs do not deteriorate the fleeces of our Lincolnshire, Lei- 

 cestershire, South Down, and other sheep. Wool grows from 

 papillae within follicles like ordinary hair, but is delicate and 

 curly. Its softness is due not a little to the yelk secreted by 

 the skin, and which amounts in weight to about half an 

 unwashed fleece. Vauquelin has shown that the yelk is 

 composed, Firstly, Of a soapy matter with a basis of potash, 





