VI.] 



CILIATED EPITHELIUM. 



137 



marble and dilute hydrochloric acid, and by means of a caoutchouc 

 tube it is conducted to a glass gas-chamber (fig. 97, C), over which 

 the preparation of cilia on a cover-glass is inverted. 



If it be preferred, the following moist chamber, by Ranvier, for 

 studying the action of gases may be used. It consists of a brass box 



FIG. 97. Gas-Chamber for Studying the Action of Gases on Cilia. A. Inlet ; 

 B. Outlet-tube; C. Glass gas-chamber. 



about the size of a microscopical slide, and perforated at the centre 

 by an aperture 2 cm, wide, which is closed below by a plate of glass. 



FIG. 98. Ranvier's Moist Chamber for Applying Gases to a Preparation. 



Iii the centre of the aperture is fixed a plate of glass (fig. 98, a), less 



in diameter, thus leaving a circular trench all round (b). Moreover, 



the height of this circular plate of glass is 



less than the height of the brass box by at 



least -iV-h inm - ^ ne k x is perforated by 



two tubes, through which the gases can 



be conducted to the preparation, which is 



placed between the top of the circular 



glass disc and the cover-glass which covers 



in completely the aperture in the brass 



box. In this way the gas or vapour can 



be applied, to a preparation still in a normal 



fluid medium. 



(a.) If carbon dioxide be used, observe that it rapidly arrests the 

 movement of the cilia and renders the cells granular, probably from 

 the precipitation in them of paraglobulin. 



Ciliated Cells from tlie 

 Mucous Membrane of the 

 Hani Palate and (Esophagus 

 of the Frog. Dilute alcohol 

 and pirro-carniine, x 303. 



