On Changes in the Sea and Their Relation to Organisms. 



247 



to indicate that these anaerobic processes constituted the metaboUsm 

 of the cassiopea. On the contrary, a great multipUcation of bacteria 

 was associated with them, and the cassiopea was partly dissolved and 



Table 21. 



could not be revived by readmission of oxygen. We may assume that 

 oxygen protects the cassiopea from the attacks of bacteria (probably 

 a,naerobes). Since the bacteria enter from the surface, it seems prob- 

 able that the cassiopea might live indefinitely on so small a supply of 

 oxygen that it is used in the superficial cells as fast as it diffuses into 

 them, and none reaches the deeper cells. If this be true, the variation 

 in oxygen consumption with variation of supply might be the expression 

 of a variation in the number of cells receiving oxygen. In other words, 

 this would be a diffusion phenomenon. 



Another hypothesis is that the tension of oxygen at the seat of 

 oxidation affects the rate. Warburg has shown that cell oxidation is 

 associated with structure and that no enzyme solution has been 

 obtained that will account for the vital oxidation of foodstuffs. If the 

 structure or surface responsible for the oxidations is designated as the 

 catalyst, it seems possible that the tension of oxygen in the immediate 

 \dcinity of the catalyst influences the rate. This influence of tension 

 on rate might still be a diffusion phenomenon, since the O2 must diffuse 

 toward the structure-catalyst or oxidase molecule. 



Owing to the excellent review of the literature on the subject of this 

 paper by Krogh, it seems unnecessary to multiply references. Roughly 

 speaking, and within physiological limits, animal oxidation is about 

 doubled with 10° rise in temperature, and this is shown here to be true 

 of Cassiopea. In other words, oxidation is an exponential function of 

 the temperature as expressed in the following equation: 



F,= F„X2(ro) 



where Vt is the velocity of oxidation at t° and Vo at 0°. This relation 

 holds approximately true for a number of chemical reactions and is 

 supposed to be due partly to change in diffusion-rate and partly to 

 loosening of bonds in the reacting molecules and to ionization. Diffu- 

 sion depends on \'iscosity and tension (osmotic pressure). A fall of 



