Tktle 16. — Chi-square test of the distribution between species of first 

 attacks in tanks 1 and k of Experiment II 



(T = Tank) 



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

 (Not significantly different) 



Table 17. — Combined attacks in tanks 1 and 4- of Experiment II 



Food 



1st 2nd 3rd 4th 5th 



6th 



7th 8th 



animals attack attack attack attack attack attack attack attack 



Total 



Bay 

 mussel 



29 



Manila 

 clam 



Olympia 

 oyster 



Pacific 

 oyster 



17 



11 





 



26 



33 



Total 31 



22 



17 



89 



19 



