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Papers from the Department of Marine Biology. 



for over two days at 20 C. (see table 11) and a shorter time at higher 

 temperatures. As only fresh water and not sea-water will call forth 

 the light, and as we know that light-production is connected with the 

 granules of the juice, the process appears similar to the cytolysis of 

 cells i. e., to the swelling and solution in fresh water of the granules 

 which the cells contain. By this means something is liberated from 

 the granules of Cavernularia juice which oxidizes with light-production. 

 Table 12 gives the results of adding various other substances, pure or 

 dissolved in sea-water, to the dark Cavernularia juice. 



TABLE 12. Effect of substances in calling forth light from non-luminous Cavernularia juice. 



Note from table 12 that light-production is not due to dilution of 

 the salts of sea-water by adding fresh-water, since m cane-sugar does 

 not call forth the light. Note also that many cytolytic substances 

 (chloroform, benzol, thymol, etc.) give light, but not the oxidizing 



