33 



On the Hairs of Indian Bats. By M. C Cooke. 

 (Read January 24iA, 18G8.^ 



For five-and-twenty years an object has been known to micro- 

 scopical observers as the " Hair of Indian Bat," and during that 

 period, if efforts have been made to discover its source, those 

 efforts have not been crowned with success ; for it is still unknown 

 what species of bat yields the hairs which are employed as test 

 objects. Full of hope that this species might be discovered, the 

 investigations which led to the production of this paper were 

 undertaken. Facilities occurred for examining the hairs of a large 

 number of well authenticated species of Indian Cheiroptera, and 

 the result of this examination forms the subject of the present 

 commimication . 



Before proceeding with the investigation, I may be permitted to 

 summarise what has been written on the subject, so that it may 

 be seen how far my observations agree with those of other observers 

 who have preceded me. Although bats' hair was known to be an 

 interesting microscopic object thirty or forty years ago, I think 

 that there is no special mention of the hair of an Lidian bat, or of 

 any other bat's hair wholly resembling it, until Mr. John Quekett 

 brought the subject under the notice of the Microscopical Society 

 of London, on the 20th October, 1841, as recorded in Cooper's 

 Microscopical Journal (p. 158), and afterwards printed in full in 

 the Microscopical Transactions (vol. i., p. 58). 



As these "Transactions" are not common, and as the observa- 

 tions there made are of importance in this enquiry, I shall extract 

 those portions to which I may hereafter allude. After describing 

 the structure of hair in general, he says : — " Having stated thus 

 much on the growth of hair, I shall proceed at once to the exami- 

 nation of that of the bat tribe. Of sixteen species of these animals, 

 the hairs of which I have examined, all were analogous in struc- 

 ture to one or other of the forms represented. They are charac- 

 terized by the shaft presenting at intervals peculiar raised mark- 

 ings, which are arranged sometimes transversely, at others 

 obliquely, to the axis of the hair; in some specimens they project 

 a considerable distance from the general surface, and the true shaft 

 of the hair appears between them at certain intervals. Having, on 



