RELATION OF BURSARIA TO FOOD 



23 



TABLE 6 



Experiment III 



Set 1 : Stimulated 



A 

 B 

 C 



NUMBER OF GRAINS EATEN BY BACH INDIVIDUAL 



71 

 9 

 5 



5 1 



3: 3 



5 



114 

 8 



96 

 127 

 59 



AVG. PER 

 IND. 



gratns 

 3.2 

 4.0 

 1.96 



Total average. 



3.5 



Total average. 



The effect of mechanical sthnulation must be emphasized be- 

 cause it shows that in any work of this nature it is necessary to 

 handle the organisms gently. This relation must be inferred to 

 apply to work on other Infusoria also, at least to some extent. 



c. Effect of temperature on feeding. 



Experiment IV. Thirty individuals starved twenty-four hours, were 

 placed in each of six vials. Each vial contained 5 cc. of tap water. 

 These vials were now placed in large dishes containing water kept at 

 the desired temperatures. The latter were read on a small thermometer 

 set inside of each vial. Equal quantities of fresh yolk suspension were 

 added when the temperature had reached the desired point. They 

 were fed fifteen minutes (table 7). 



TABLE 7 

 Experiment IV 



deg.C 



5 



10 



15 



20 



35 



39] 

 to 

 40 



NUMBER OF GRAINS EATEN BY EACH INDIVIDUAL 



I 



o! 0| 



0] 



l! 3 

 4J19 



3! 4 



! I 



0! 



Oi Oj 

 

 Oj 

 213114 

 1316 4 



0; 



oj 



4 0: 3 



5 9: 2 

 12! 9 





 

 2 3 

 4 5 

 8 13 





 3 



52 

 195 

 241 



All died in from 5 to 10 minutes 



