PARAMOECIUM POSSESSING EXTRA VACUOLES 



301 



did not begin in the majority, they nevertheless drop toward the 

 base line noticeably. Chart 5 is a striking confirmation of the 

 two previous charts. Six cultures were followed and the re- 

 sults plotted on the one chart. The fours play a comparatively 

 unimportant part and will not be discussed. The X formed by 

 the crossing of the unbroken line representing the two vacuoled 

 animals falling from high on the axis of ordinates to the axis 

 of abscissas by the dotted curve of the three-vacuoled para- 

 moecia rising from low percentages to higher ones is very marked. 



Chart 5 The description of this chart is on page 301. 



The numbers on the various curves indicate the number of the culture and 

 not the number of the vacuoles as on the other charts. The same method of 

 designating the various forms is used as on the other graphs. 



Still more interesting are the results obtained from March 15 

 on and represented on this graph. Cultures 1, 3 and 5 were 

 undisturbed while fresh hay infusion was added to cultures 2, 

 4 and 6. The results for each three cultures were averaged and 

 plotted. 1, 3 and 5 continued as before while 2, 4 and 6 due 

 to the acceleration of the division rate caused by the addition of 

 fresh infusion show a rapid increase of two-vacuoled paramoecia 

 with a corresponding drop in the threes. By April 6, however, 

 the rate of increase had slowed down and the curves of the one 

 set of cultures were very close to the corresponding curves of 

 the other set. Chart 12 while drawn primarily to illustrate the 



