TRANSITION TO ANAEROBIOSJS 



149 



Oxygen tension in cc. per liter 



Fig. 4. Dependence of glycogen consumption on oxygen tension in Tu- 

 Mfeoc. (According to Dausend, 1931.) 



able. "Whether technical errors are responsible for the 

 exceptional cases (Table 20) in which the respiratory 

 quotients did not increase at lowered oxygen tension, 

 as in Rliizostoma, Carmarina and Cestus, or whether 

 these animals are incapable of anaerobic metabolism is 

 a matter of conjecture. 



Maloeuf (1937) expressed the dependence of the res- 

 piratory quotient EQ on the oxygen tension P by the re- 

 lation EQ =K/P, where K is a constant (P is the prod- 

 uct : 22.4 X molar concentration X T/273 atmospheres, T 

 being the absolute temperature). The value of the con- 

 stant K is 25 X 10"^ for Gambarus bartoni and Cambarus 

 clarkii, 44 X 10"^ for Asterias forbesii, and 77 X 10"* for 

 Mytilus edulis. This formula, however, can be applied 

 only within a limited range of oxygen pressures : in the 

 crayfish between 0.00025 and 0.0045, in the starfish be- 

 tween 0.0020 and 0.0056 and in the mussel between 0.0016 

 and 0.0064. Above these ranges the respiratory quotient, 

 of course, remains more or less constant since the maxi- 

 mal rate of oxidation is reached. 



