58 PLATE XXVI. 



This fpecies of Vorticella appears, v/ithout the afllftance of a micro- 

 fcope, as fmall black fpecks, fwunming on the water, particularly in 

 meadows which are inundated. They are confl-antly in motion; and 

 two fmall white hooks are perceptible by glaffes at i — i ; by the help 

 of thofe it is fuppofed to fwim, or they may inclofe fome rotatory or- 

 gan. The infeil is opacjue. 



PLATE 



