DESTRUCTION OF ONE SPECIES BY ANOTHER 



119 



Paramecia, and suitable physicochemical conditions for the very- 

 sensitive Didinium. It is self-evident that if at the very beginning 



!o 



a) 



JS Number of Didinium 



f Volume of Didinium zo 



■ -jL_ b 



Number of Paramecia 



/ 



So 



<t> 



to 



^3o 



J" 



lot 



to 



€0 



*o . 

 Zo . 



Number of Paramecin 

 I 



(c) 



Numter of Didinium , ,- — 



y ° 

 /A / 



/ Volume of 

 / Oidimunx 



-Jt — s_ 



Number of 

 / Paramecia 



Number of 

 Paramecia 



Paramecium 

 separately 





Days 



Fig. 29. The destruction of Paramecium caudatum by Didinium nasutum. 

 (a) Growth of P. caudatum alone, (b) Didinium is introduced at the very 

 beginning of growth of Paramecia population, (c) Didinium is introduced 

 after 24 hours, (d) Didinium is introduced after 36 hours, (e) Didinium is 

 introduced after 48 hours. Numbers of individuals pro 0.5 c.c. 



we set up unfavorable conditions under which Didinium begins to 

 degenerate, and as a result is unable to destroy all the prey, or if the 



