PARAMECIUM. 



THE SLIPPER ANIMALCULE. 



PARAMECIUM is found in water containing decaying 

 organic matter, i. e., in infusions of organic matter hence 

 the name infusoria, the class to which the animal belongs. 

 In nature Paramecium will be found in almost any ditch 

 or pond which contains much organic matter. In a jar 

 containing an infusion of hay the paramecia are usually 

 found near the surface and often in a ring around the edge 

 of the dish. Mount a drop of water from this region of the 

 dish, first placing a thin layer of cotton on the slide to trap 

 the animals, or a solution of gum to lessen the activity. 

 Examine with the low power. 



I. Morphology. 



1. Form. Are there individual differences in size? Can 

 the animals be seen with the naked eye? In outline the 

 animal is elliptical or oval, often rather slipper-shaped, 

 whence comes the name "slipper animalcule." Is the shape 

 constant under all conditions? Watch one while it is pass- 

 ing through a narrow space. Is the body rigid or flexible? 

 Are there definite anterior and posterior ends? If so, how 

 are they distinguished? 



With a piece of clay make a model of the paramecium. 

 Be careful to get the right proportions and shape. 



2. Structure. Along one side of the animal is a groove 

 which leads to a mouth opening. The most satisfactory 



