PHYLUM PROTOZOA 



33 



(2) Sporulation is apparently a rare process of multiplication in 

 Ameba. First the pseudopodia are drawn in and the animal 

 becomes spherical; a three-layered cyst is then secreted. By 

 successive divisions of the nucleus from five hundred to six 

 hundred daughter nuclei are produced. Cell walls then appear, 



Fig. 11. — Ameba polypodia dividing by binary fission. (From Parker and 

 Haswell, after F. E. Schulze.) 



dividing the Ameba into as many cells as there are nuclei. These 

 Amebulce, or pseudopodiospores, as they are sometimes called, 

 break out through the cyst and become recognizable as Ameba 

 Proteus in about three weeks. 



The Behavior of Ameba. — The sum total of all the move- 

 ments of an animal constitute what is known as its behavior. 

 In Ameba these movements may be separated into those con- 



