158 PROCEEDINGS OF THE MICROSCOPICAL SOCIKTY OF LONDON. 



some pears, Turpin once found a great number of the genus Acarus, of 

 an oval shape, furnished with claws close to the beak, and four poste- 

 rior filaments, presenting nothing very remarkable except four articu- 

 lated legs, terminated by a single slightly-arched nail. The young 

 individuals, after molting, assume their eight legs. Mem. de I'Acad. 

 Instit. Paris, 1840, p. 56. 



PROCEEDINGS OF THE MICROSCOPICAL SOCIETY OF LONDON. 



October 20th, 1841 .Prof. R. Owen, F.R.S., &c., President, in the Chair. 



MR. THOMPSON, of Belfast, forwarded some Fossil Infusoria from earth, 

 obtained at Cork. 



Mr. J. Quekett read a paper " On the minute structure of Bat's Hair." 

 After alluding to the views entertained by Hunter, Mandl, Busk, and 

 others, as to the formation and mode of growth of hairs generally, 

 the author stated that his attention was directed to those of the bat tribe, 

 in consequence of having on more than one occasion used a knife to 

 separate them from the skin ; on subsequent examination it was 

 seen that the curious markings on their surfaces, which render these 

 hairs so interesting, were destroyed in some parts, but were still present 

 in others. By repeating the scraping process, it was found that minute 

 scale-like bodies were detached, which were not unlike in shape the scales 

 on the wing of a butterfly, but were very much smaller, and presented 

 no trace of striae on their surfaces; it was on the arrangement of 

 the scales, and on their being more prominent in some species than in 

 others, that the beautiful appearance of bat's hair depended. The 

 scales might be procured either by scraping the hair with a knife, in a 

 direction from the apex towards the root, or more easily by pressing 

 them between glasses previously moistened by the breath. Many of 

 them appeared to terminate in a quill, like that observed on the butter- 

 fly's scale ; some few were flat, whilst others were curved so as to fit 

 the shaft of the hair, and presented a serrated edge. The scales were 

 absent near the bulb, but abounded in all parts of the shaft situated 

 above the skin ; and when removed from many of the larger hairs, the 

 fibrous nature of the shaft, and its cellular interior were well displayed. 

 Mr. Quekett spoke of the hair of an Indian bat, of which a small por- 

 tion had been given him by Mr. Powell, in which, without any prepara- 

 tion, the scales could be beautifully seen, both detached and still adhe- 

 rent to the shaft ; and he was led, from repeated observation, to consider 

 a bat's hair as composed of a shaft invested with scales, which are de- 

 veloped to a greater or less degree, and vary in the mode of their 

 arrangement in the different species of these animals ; and concluded by 

 stating, that bats resembled quadrupeds principally in their mode of 

 reproduction, and birds in their mode of progression, but resembled 

 both in the structure of their hair. 



Mr. Bowerbank called the attention of the meeting to a source of 

 fallacy he had detected in using strong solutions of salt and water, for 



