460 



RESEARCH IN PROTOZOOLOGY 



20 



15 



10 



8 PM. 



12P.M. 



4A.M. 8A.M. 



TIME OF DAY 



12A.M. 



4PM. 



Fig. 31. — Growth of Plasmodium prcscox in the asexual stage. (Arithmetic 



scale.) 



Substituting these values in the general equation 



log y =^ a -\-hx 

 and solving for a and h we have 



log 1.14 = .0569049 = a 

 log 20 = 1. 3010300 = a + 20^ 

 a = .0569049 

 2oh = 1. 244125 1 

 b = .0622063 

 By considering the fact that 

 log A ^= a and 

 log B ^^ b we find that 

 A =: 1. 14 and 

 B= 1. 1540 

 Thus we may write the equations as 



^_ jQ .05G9 + .0.i224^. _ j_j^ (l.l54)^ 



The important constant in this series is B, since it tells us that 

 the average size of these parasites at any time is 1.154 times as 

 great as the size an hour earlier ; thus we may say that these 

 organisms increase at a rate of fifteen per cent per hour. 



