34 M. C. COOKE ON THE HAIRS OF INDIAN BATS. 



more than one occasion, failed in pulling the hairs out of the skin 

 with my fingers, in order to obtain some, a knife was used, and the 

 hair held firmly between its edge and the thumb. On examination 

 of these hairs afterwards, it was found that they were altered in 

 character, the markings on them, which were so peculiar, being de- 

 stroyed in some parts, and left undisturbed in others ; they ap- 

 peared as if something had been taken away from them in certain 

 points. This led me to expect that the curious surfaces which these 

 hairs present might be owing to a development of scales on their 

 exterior, and repeated examination has convinced me of the truth 

 of this supposition. I have since found that by submitting hair to 

 a scraping process, minute scale-like bodies, tolerably constant, as 

 far as regards their size and figure, can be procured, so that bats' 

 hair may be said to consist of a shaft invested with scales, which 

 are developed to a greater or less degree, and vary in the mode of 

 their arrangement in the different species of the animal. The sur- 

 face of that part of the hair nearest the bulb is nearly free from 

 any trace of scale, but as we proceed towards the apex the scaly 

 character becomes more evident. In many hairs the scales lie in a 

 direction at right angles with the shaft, and one scale forms a com- 

 plete band around the shaft ; in others they run with varying de- 

 grees of obliquity, giving a true spiral character to the hair, whilst 

 in many others, scales may be seen in all stages of development. 

 The larger kind of hairs, such as are procured from the various 

 species of vampire, are generally of a dark yellow colour, and are 

 comparatively smooth externally, but exhibit a cellular structure 

 internally. Many of the scales are not unlike — in shape — those 

 from the wings of butterflies, but are much more minute, and ex- 

 hibit no trace of striae on their surfaces ; but those taken from 

 dark coloured hairs have the colouring matter deposited upon them 

 in small patches. 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. By scraping, many of them wUl 

 be detached separately, but in some few cases as many as four or 

 five will be found joined together. 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. 

 " As far as my observations have gone, they lead me to believe 

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

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



