112 



AN INTRODUCTION TO ZOOLOGY 



TABLE III 



DIAGRAMS ILLUSTRATING THE METHODS OF REPRODUCTION IN PROTOZOA 



AND METAZOA 



A. A simple Protozoon (Ameba). 



psp 



CELL DIVISION 



(Binary Fission) 



An indefinite number of 



generations. 



ENCYSTMENT AND SUBSE- 

 QUENT CELL DIVISION 



(Sporulation) 



Many pseudopodiospores (psp) 

 ' (young Amebce) produced. 



CELL DIVISION 



(Binary Fission) 



An indefinite numbei 



of generations. 



B. A simple Protozoon (Paramecium). 



CELL DIVISION TEMPORARY CONJU- 

 ( Binary Fission) CATION 



An indefinite num- (Fertilization) 

 her of generations. Each cell fertilizes 

 the other. 



CELL DIVISION CELL DIVISION 

 (Period of Recon- (Binary Fission) 

 struction) An indefinite num 



Each fertilized cell her of generations, 

 gives rise to four 

 normal animals. 



