464 



LORANDE LOSS WOODRUFF AND RH. ERDMANN 



division spindle. This proves that in generation 4182 the com- 

 plete extrusion of chromatin bodies will be completed and the 

 'reduction' divisions of the micronuclei and their degeneration 

 must also occur here during the thirty-six hours that this cell 

 persists as an individual. The low division rate at this point 

 indicates that the profound nuclear changes temporarily inhibit 

 the reproductive acitivity. The animal undergoing the next 

 division (4182-4183) was not preserved but evidently would 

 have shown each of the arising cells in the climax of the process 



Ci 



VI 4140 



Ct 



c. 



VI 4141 VI 4142 



Text figure 7 



C* 



VI 4143 



with one or two micronuclei and numerous chromatin bodies. 

 However, one of the completed products of this division, 4183d 

 generation (D3), shows the two macronuclear anlagen completely 

 formed. The next stages (4185i, 41852, 4187) show the distri- 

 bution of the chromatin bodies. Cell 4184 was not preserved 

 but evidently it had one macronuclear anlage, so from gener- 

 ation 4182 to 4192 (D7) with one chromatin body, we have the 

 process characterized physiologically by the lowering of the divi- 

 sion rate in the 4182d to 4183d generations when reproduction was 

 deferred for about thirty-six hours, and then the sudden acceler- 



