386 DEPTHS OF THE OCEAN chap, m 



biologists favour the theory and others oppose it ; some of 

 them have pubHshed the results of special studies, particularly 

 of the nutrition-processes of animals, all of which have been 

 of service to the cause of science, though they have not 

 succeeded in deciding this question. 



Lohmann and C. G. J. Petersen have maintained that 

 organic detritus may be of intrinsic importance for the nutriment 

 of animals, as well as plants, and they have demonstrated that 

 organic detritus from the land is present in fairly large quantities 

 in waters like the Baltic or off the coasts of Denmark. We 

 have reason, therefore, to expect extremely interesting results 

 from the work of the Danish biologists on organic detritus in 

 the water and in the deposits at the bottom of the sea. But out 

 in the open sea this detritus is only met with in inconsiderable 

 quantities, as our centrifuge-samples showed us on board the 

 " Michael Sars." I do not, of course, include inanimate organic 

 substances, such as excrements or the empty chitin-coverings 

 of copepods, which form a part of the circulation of nutritive 

 substances through the pelagic organisms. Organic fragments, 

 not actually derived from pelagic organisms, either do not occur 

 at all in the open sea, or, if they do, are not worth taking into 

 consideration. 



H. H. G. 



