144 CONJUGATION, MATURATION, AND FERTILIZATION 



characterized as follows: Two are destined to degenerate as "reduc- 

 tion nuclei," four become the centres of shell formation of the spores, 

 four become centres of pole capsule formation, and four remain as 



FIG. 60 



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C ,' 



* . * 

 * ' 













 I 



* * 



_ 



Autogamy in Ameba proteus. In upper figure secondary (gametic) nuclei are shown 

 emerging from the primary nuclei. In central figure is pictured the union of gametic nuclei 

 together with some undeveloped ones in a primary nucleus. In lower figure is shown the 

 mass of sporoblasts which develop from the fertilized gametes. (After Calkins.) 



