PBACTICAL ZOOLOGY. 



Chapter I. 

 THE PROTOZOA. 



A PEOTOZOON is an aDimal which consists of only one cell, 

 the morphological equivalent of a single cell of any of the 

 tissues of a higher animal. 



Protozoa are always of small size, and are usually micro- 

 scopic. 



I. AMCEBA. 



This protozoon is found at the bottoms of freshwater 

 pools, and in damp situations. It may be obtained in autumn 

 by placing the dying stalks of the bean plant, or fallen leaves 

 of most trees, in water for a few days. Its indefinite and ever- 

 changing shape is characteristic, and has gained for it the 

 name ' proteus animalcule.' There are several forms, the 

 largest of which are just visible to the naked eye, while others 

 are exceedingly minute. 



Place a drop of water containing Amosbce on a slide ; 

 cover ; and search for the animals with a low power of, the 

 microscope. When fmmd, examine them with a high poiuer. 



A. General appearance^ 



The animal is an irregular mass of protoplasm, running 

 out into blunt processes or pseudopodia, the protrusion and 



