SELIG HECHT 685 



2. The relation between the latent period and the temperature is 

 adequately expressed by the Arrhenius equation, for temperatures 

 below 21°C. Above this temperature, the latent period becomes 

 increasingly longer than is required by the Arrhenius formula when 

 fi = 19,680. 



3. These deviations, occurring above the highest environmental 

 temperature of My a, are explained on the assumption that the 

 principal product formed during the latent period is inactivated by 

 heat. 



4. Calculation of the velocity of the hypothetical inactivation 

 reaction at different temperatures shows that it also follows the 

 Arrhenius rule when n = 48,500. This value of n corresponds to 

 those generally found for spontaneous inactivations and destructions. 



BIBLIOGRAPHY. 



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Chick, H., and Martin, C. J., On the "heat coagulation" of proteins. Part II, 

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Duclaux, E., Traite de microbiologic, Paris, 1899, ii. 



Hecht, S., (c) Sensory equilibrium and dark adaptation in Mya arenaria, J. 

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