SELIG HECHT 



339 



Two sets of experiments were made, the first with five animals and 

 the second with four animals. The results were identical in both 

 series. Indeed the individual animals gave essentially the same re- 



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I 



I 



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Intensify — /^eter-Candle^ 



Fig. 1. Data showing the effect of variations in intensity at constant exposure 

 on the duration of the reaction time of Mya. Each point is the average of fifteen 

 readings, three each on five animals. 



TABLE I. 

 Relation between the Latent Period and the Intensity at Constant Exposure. 

 Experiments 121 to 125 inclusive; exposure, 0.133 second. 



suits as the averages for either set of experiments. Fig. 1 and Table I 

 give the data for the first set of five animals. Each reaction time in 

 the table is the average of fifteen observations, three on each of the 



