SEA-FISHERIES LABORATORY. 407 



The considerable amounts of fat in the tissues of the 

 fish and octopus after a whole month of fasting are 

 remarkable; the corresponding figures in the two lobsters 

 are low, but a comparison with the figures for normal 

 freshly-caught lobsters as shown in the succeeding paper 

 show that there is no very great reduction in fats as a 

 result of the fasting, the normal percentage of fat in this 

 animal being a low one. 



It is of interest to consider the figures from the point 

 of view of Putter's theory that such marine animals 

 obtain a large percentage or the whole of their nutrition 

 not in particulate form, but as dissolved organic matter. 



In his earlier work, through the use of faulty 

 analytical methods, this observer claimed to have demon- 

 strated a considerable amount of dissolved organic matter 

 in sea-water, reaching to as much as 134 milligrams per 

 litre. 



At a later period Putter reduces his assumption of 

 the content of dissolved organic matter in sea-water to 4 

 or 5 milligrams per litre, chiefly as a result of the re- 

 determinations of the maximum possible amount of 

 dissolved organic matter by Henze as lying below 3 to 

 4 milligrams per litre. Henze states in his paper, how- 

 ever, that the amount is so small as to be indeterminate 

 and within the limits of experimental error. He does not 

 state that sea-water actually contains 3-4 milligrams of 

 organic matter per litre, although Putter assumes tins as 

 a deduction apparently from Henze's work in all bis 

 later papers. From our own previous experiments, we 

 feel convinced that organic mailer in solution is 

 practically absent from pure sea-water. Putter, while 

 agreeing thai the content of sea-water in dissolved organic 

 matter is much less than his original estimate, still 

 adheres to his original view, in spite of the change 01 



