Unicellular^ Microscopic Animals 347 



traction. A new one forms by the fusion of droplets of liquid. Indigesti- 

 ble and partially digested food particles are egested at any point of the 

 surface, there being no special opening to the outside. Ordinarily, the 

 wastes include solids, fluids, minerals, urea, carbon dioxide, etc. 



/. 



Fig. IGl. — Reaction of Amoeba to light, in which it moves away from the 

 source of light. The arrows at a, b, c, and d indicate the successive directions of 

 the light and the numbers indicate the successive positions occupied by the 

 Amoeba. (From Jennings: Behavior of the Lower Organisms, published by 

 Columbia University Press.) 



Coordination and Sensory Equipment. — Even though an amoeba is 

 small and rather simply constructed, its different parts must be properly 



