234 



THE AMERICAN NATURALIST 



[ Vol. L 



is hoped that future offspring may be obtained to con- 

 tinue this strain. The times for the fifteen trials do not 

 always correspond with the times for the last ten trials. 



Thus No. 66 has for the fifteen trials an average time of 

 113 sec, but in the last ten trials reduced the time to 17 

 sec. The capacity of the mice can only be finally deter- 

 mined after the same individual has been tested by dif- 

 ferent methods. 



