EFFECT OF CONJUGATION 



311 



two weeks each, also for the total, thirty-one days; and for the 

 entire sixty-eight days from the beginning. 



As table 14 shows, the progeny of the conjugant line 7 a still 

 reproduced somewhat more slowly than did the non-conjugant 

 lines, during these last four weeks of the nine weeks during which 

 the experiment had lasted. The average in the conjugants is 

 less in each of the partial periods, as well as in the period as a 

 whole. The average rate of fission is somewhat less in all lines 

 than during the first five weeks; this is a common result of con- 

 tinued cultivation on slides. 



In the third portion of the experiment two of the lines of non- 

 con jugants (1 a and 1 h) and one of the lines of conjugants (7 a) 



TABLE 13 



Experiment 6. Paramecium aurelia. Comparative number of fissions in six lines 

 derived from conjugants and in six derived from non-conjugants {split pairs), 

 from a watch glass culture of the race k; for five iveeks and two days. The fissions 

 are given by days for the first nine days; for the rest only by the week. The num- 

 bers give the number of divisions that occurred in the time specified. The first 

 week is counted from March 8 to March 14- (d = died out.) 



Mean per week, 8.80; mean for 37 days, 45.00 



B. Those that did not conju- 

 gate 



1 a 



b 



2 a 



b 



3 a 



b 



Mean per week, 10.20; mean for 37 days, 53.33 



58 

 52 

 59 

 50 

 54 

 47 



THE JOURNAL OK EXPERIMENTAL ZOOLOGY, VOL. 14, NO. 3 



