60 



merely to lay the hair on a slip of glass, then, having breathed upon 

 it, press another glass upon it three or four times in succession, 

 which will cause the scales to be detached in small quantities, and 

 become adherent to the glass. In all cases, if possible, the hair 

 should have been first washed with ether, which will remove much 

 of the greasy matter with which most hairs abound. 



Many of the scales are not unlike in shape those from the 

 wings of butterflies, but are much more minute, and exhibit no 

 trace of striae on their surfaces (fig. 11) ; but those taken from dark- 

 coloured hairs have the colouring matter deposited upon them in 

 small patches (fig. 12). In some cases they appear to terminate in 

 a pointed process, like the quill observed in butterflies' scales ; and 

 in others the free margin is serrated (fig. 13). By scraping many 

 of them will be detached separately, but in some few cases as many 

 as four or five will be found joined together (fig. 14) : in the larger 

 hairs the cellular structure of the interior, as well as the fibrous 

 character of the shaft, can be well seen when the scales have been 

 removed (fig. 15). The difference (in appearance) of the hair near 

 the bulb where it is smooth, and towards the apex where it is scaly, 

 besides proving that the scales must grow after the shaft has appeared 

 above the cuticle, points out the analogy between this part of a hair 

 and the quill of a feather ; and it would follow that the addition of 

 new matter at the base alone would not account for the after growth 

 of the scales : it would seem more probable that the view of the sub- 

 ject entertained by Dr. Mandl and Mr. Busk* was the more correct, 

 viz. — that the hair has a vitality of its own, independently as it were of 

 the bulb, — in fact, a kind of circulation ; and by this means the scales 

 on its surface grow, and continue to grow after the hair has appeared 

 above the cuticle. If there were not this deficiency of scales at the 

 base of the hair, the shaft being tightly embraced by the neck of the 

 follicle, the scales from their position would certainly be an obstacle 

 to the easy passage of the hair above the skin. It would be an inte- 

 resting subject for examination to take the hair of a very young ani- 

 mal, and measure the distance of the scales from one another, and 

 their length, and to notice as the animal grew whether there was any 

 increase in their size, and whether they became more distant from 

 each other : as far as my observations have gone they lead me to be- 

 lieve that the smaller the hair is in diameter the more closely packed 

 are the scales ; and it would account at once for some appearances 



* Microscopic Journal, vol. i. p. 2'>. 



