CHAPTER XXXI. THE SLIPPER- ANIMALCULE. 

 (Paramecium aurelia.) 



1. Form and Mode of Life. Paramecium is a minute 

 organism very common in fresh water where there are 

 decaying vegetable remains. It is just visible to the naked 

 eye as an elongated whitish spot. Microscopic examination 

 soon shows that its body consists of a single cell, as does 

 Amreba ; but two striking differences from the latter type 

 are at once seen. Firstly, Paramecium has a definite and 



Fig. 202. PARAMECIUM. 

 (After Parker.) 



constant shape and secondly, it swims about through the 

 water (rotating as it does so) or glides over the surface 

 of any solid with what appears to be great rapidity as 

 compared with the slow crawl of Amffiba. 



The shape of Paramecium (fig. 202) is not unlike that of 

 the slipper which gives it its common name that is to saj T , 

 it is elongated in one direction, rounded at one end and 

 bluntly pointed at the other, while on one of the flattened 



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