1!sLble l4. — Chi-square test of the distribution "between species of first attacks 

 made in tank 2, Experiment I and check tank 3, Experiment II 



Chi-square value of 1.04, with 3 degrees of freedom. 

 (Not significantly different) 



Ikble 15. — Chi-square test of the relative numbers of different types of 

 organisms attacked in tanks 1 and h of Experiment II 



Chi-square value of 0.96, with 3 degrees of freedom. 

 (Not significantly different) 



18 



