INFUSORIA. 415 



round in a circle, with many gyrations, much like the pretty 

 little polished beetles (Gyrinus) that play in mazy dances 

 on the surface of a pool. The two extremities seem covered 

 with minute pits or stipplings, but colourless ; the central 

 part is occupied with yellowish granules of different sizes. 



I once witnessed the dissolution of one of these animals 

 under peculiar circumstances. Two or three stems of an 

 aquatic plant had become crossed in the live-box so as to 

 form an area, into which the Stylonychia had somehow 

 introduced himself. There was just room for him to 

 move backward and forward without turning, and the 

 space was about three times his own length. Within this 

 narrow limit he impatiently continued crawling to and fro, 

 moving his uncini with great rapidity, and showing their 

 extreme flexibility; for, as he applied them now to the 

 stem, now to the surface of the glass, these whip-like 

 uncini were sometimes bent double. The so-called styles 

 at the posterior extremity, though less frequently used so, 

 were yet occasionally bent and applied to the surface as 

 feet, so that they are certainly not inflexible as supposed, 

 nor do I see any essential difference between them and 

 the uncini. The whole body was flexible, taking the form 

 of any passage or nook into which it was thrust, yet 

 recovering its elasticity immediately the pressure was 

 removed. Its proper form appeared to be convex above 

 and concave beneath, rather than flat. After having been 

 thus employed about half-an-hour under my observation, 

 it became still, moving only its cilia, when I left it a little 

 while, and on my return found that it was dissolved ; the 

 outline having entirely disappeared, and nothing being left 

 but the granules, and globular vesicles, that had constituted 

 its viscera, some of which still contained the carmine 

 which had been very perceptible -in the living animal. 

 This was the more remarkable, as there was plenty of 

 water. It looked like suicide, — a spontaneous choosing 

 of death rather than hopeless captivity. 



