REPRODUCTION 

 Table 5. — Continued 



Protozoa 



Number of 

 chromosomes 



Observers 



vision, giving rise to daughter blepharoplasts and kinetosomes that 

 become organized into characteristic locomotor organelles. Morpho- 

 genesis in the apostomes (Chatton and Lwoff, 1935; Lwoff, 1950); 

 mechanism of morphogenesis in ciliates (Faure-Fremiet, 1948; Guil- 

 cher, 1950; Weisz, 1951, 1951a). 



Binary fission. As in metazoan cells, the binary fission occurs very 

 widely among the Protozoa. It is a division of the body through 

 middle of the extended long axis into two nearly equal daughter 

 individuals. In Amoeba proteus, Chalkley and Daniel found that 

 there is a definite correlation between the stages of nuclear divi- 

 sion and external morphological changes (Fig. 68). During the pro- 

 phase, the organism is rounded, studded with fine pseudopodia and 

 exhibits under reflected light a clearly defined hyaline area near its 

 center (a), which disappears in the metaphase (b, c). During the 

 anaphase the pseudopodia rapidly become coarser; in the telophase 

 the elongation of body, cleft formation, and return to normal 

 pseudopodia, take place. 



In Testacea, one of the daughter individuals remains, as a rule, 

 within the old test, while the other moves into a newly formed one, 



