468 



EVENESTGS AT THE MICROSCOPE, 



is always an angle, until the rim of tlie cell is in con- 

 tact with the plant to which it is attached. This action 

 is instantaneous. Presently, however, it rises, and re- 

 sumes its former position, and then the mouth of the 

 cell slowly opens, and the animal again protrudes, the 

 cilia appearing first, and finally the head or front part 

 of the animal, which is then opened and begins to 

 rotate. 



Yery similar to this ai*e the Vaginicolce, but the 

 cells which they inhabit are not stalked, but are im- 

 movably affixed to plants. In Y. crysiallina, the cell 

 is a tall goblet, standing erect, perfectly colourless ; 

 while in Y. decumhens, it is slipper-shaped, attached 

 along its side, and of a golden-brown hue, but still 

 quite transparent. Here is, fortunately, a group of 

 the latter species, scattered about the leaves of the 

 Nitella. 



Though, in general, both in form and habits, 

 closely like the Cothurnia^ yet the Yaginicola has 



VAOINICOLA. 



some peculiarities of interest. The cilia are more de- 

 veloped, and can be more distinctly seen than in either 

 Cothurnia or Yorticella^ forming, when in swift action, 



