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ELLINOR HELENE BEHRE. 



It appears from the two graphs, then, that worms whose sus- 

 ceptibility is tested at a higher temperature than that at which 

 they were living for a week are more susceptible than the controls ; 

 worms tested at a lower temperature than that at which they had 

 lived a week previously are less susceptible than the controls. 



Other data supporting these general conclusions are given 

 below in Table I. Here are given the results of typical experi- 

 ments differing from those pictured in Figs. I and 2 merely in 

 the length of time that the experimental worms had lived in one 

 temperature before being tested at the other. Some experiments 

 with each direction of temperature change from the living to the 

 testing one are given. Only the time of complete disintegration 

 is recorded. In Table I. the first vertical column gives the series 



TABLE I. 



* In this case the difference between experimental lot and control is greater than 

 is indicated in the table, because observation was concluded before the controls 

 were completely dead and disintegrated. 



numbers; the second column headed "acclimation temperature" 

 gives the temperature the effect of which on a second change of 

 temperature is to be tested. The third column, "acclimation 

 period," gives the length of time during which the animals are 

 kept at acclimation temperature. The fourth column, "testing 

 temperature," gives the temperature at which the animals were 

 tested. The fifth column shows whether the experimental lot is 

 more or less susceptible than the control. And the last column 

 shows the temperature at which the control worms were living 



