CLASSIFICATION OF DEPOSITS 



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the depth of water, and the nature of the organisms 

 living on the bottom and in the surface and subsurface 

 \\aters. After the detailed study of the marine 

 deposits collected by the " Challenger " and other deep- 

 sea expeditions, Murray and Renard proposed the 

 following classification : 



It has frequently been pointed out, even by the 

 authors themselves, that this classification is not 

 perfect, but no better has been as yet proposed. It is 



* Krummel has recently introduced the term ' ' hemipelagic 

 for the deep-sea terrigenous deposits, and " eupelagic " for 

 the pelagic deposits in the above classification (" Handbuch 

 der Ozeanographie," vol. i., p. 205, Stuttgart, I97)- These 

 terms have, however, been employed already to express quite 

 other facts. 



