OP ANIMALCULES. 183 



the bottom of the vessel on their backs, struggling to 

 turn themselves about. 1 am inclined to think, however, 

 that they are not scarce, but only difficult to be procured 

 from their residing in the sediment at the bottom of the 

 vessel : it is probable that, in their natural situation, they 

 attach themselves to the water plants, and are dislodged 

 in the act of being collected. 



435. The Sloth. — This curious animalcule is of a 

 dingy yellow colour, about three times the size of the 

 common wheel animalcule (396), and, like it, is capable 

 of being resuscitated, after becoming dry and apparently 

 dead : the body is cylindrical, with the anterior extremity 

 convex^ and the posterior furnished with four feet-like 

 processes, each terminated by a sharp claw. On the 

 under side are three pair of feet, resembling those of a 

 caterpillar, all of which are also furnished with a single 

 bent claw ; it never swims, and appears almost incapable 

 of supporting its own weight. Scarce. Found at the 

 bottom of infusions containing the Vortkella rotatoria. 



