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DISCUSSION 



FULTON: I noticed that the patterns were the same, but the 

 absohite numbers were very different when you grew them at 20' 

 versus 19 to 23 '. Was one of these in the hght and the otlier in the 

 dark, or anything like that? 



LYTLE: No. The animals in these experiments were all grown in 

 an aquarium room with several large windows. No attempt was 

 made to alter the normal photoperiod of light and darkness. 



FULTON: So far as you know the 19" to 23^^ versus the 20° 

 are under otherwise identical conditions, but just the temperature 

 varied? 



