RHYTHMS AND ENDOMIXIS IX PARAM/ECIUM AURELIA. 



55 



this pedigreed culture was isolated on January 7, 1915, from 

 material supplied by Dr. Florence Peebles from Bryn Mawr, Pa. 

 The culture was discontinued at the 65Oth generation on February 

 8, 1916. Fig. 3 shows the relationship of rhythms and endo- 

 mixis during the first eighty-five days of the culture when the 

 animals were being examined for the reorganization process- 

 The results fully substantiate those obtained from previous races. 

 The last inter-rhythm period shown in the diagram is apparently 

 longer than usual though it is possible that endomixis was 

 overlooked about the I5th five-day period. 



Race V. (Oxford Race.} Culture started, from material se- 

 cured at Oxford,, Ohio, on July 16, 1915, and discontinued on 

 August 7, 1916, at the i,oooth generation. The division rate of 

 the culture is shown in Fig. 4 for the first 44 five-day periods of 



its life. During this time nine rhythms occurred at each of 

 which endomixis w r as observed. It is hoped that readers who 

 may possess doubts concerning rhythms and endomixis will 

 carefully consider this graph. 



Race VI. (Woods Hole Race.) This race was obtained by 

 Dr. G. A. Baitsell at Woods Hole, Mass., and its pedigreed 

 culture was begun on August n, 1915, and discontinued on Jan- 

 uary 14, 1916, at the 305th generation. Fig. 5 gives the graph 

 of the division rate of this culture throughout its existence. 1 



1 The division rate is plotted consistently one quarter of a division per day too 

 fast for every five-day period, owing to a draughtsman's error. An E should be 

 inserted in the first period. 



