NATURAL HISTORY STUDIES 



form of dust ! So a pound of carnivorous fish 

 b'ke a cod requires 1,000 Ib. of sea-grass. If there 

 be fewer links in the House-that-Jack-built nutri- 

 tive chain, the pound of flesh will be, so to speak, 

 cheaper. Thus a pound of plaice is said to require 

 to begin with only 100 Ib. of vegetable material. 

 But the main fact is clear that just as all flesh is 

 "grass," so sooner or later all fish is "seaweed." 



Consumers 



The natural consumers of the wealth of the sea 

 are the animals, but these are not all on the same 

 platform. First, there are true carnivores, like 

 most fishes, all cuttlefishes, many Gasteropods 

 (like whelks), many crabs, most starfishes, and so 

 on down to sea-anemones. Second, there are 

 vegetarians, like periwinkles and limpets, on the 

 shore, and some of the open-sea animals like the 

 Copepod Crustaceans. Third, there is an enormous 

 multitude depending mainly on crumbs or detritus. 

 This classification is not, of course, to be taken too 

 rigidly, for it will be readily understood that many 

 a marine carnivore may also utilize animal particles 

 just as a Golden Eagle, with a preference for fresh 

 grouse, does not always hold carrion in disdain. 

 Similarly, some marine vegetarians are not too 

 scrupulous as to the constituents of the sea-soup 

 they enjoy. The probability is that the distinction 

 between carnivore and vegetarian is not so important 

 as that between animals with and animals without 

 hard gripping and chewing mouth-parts. This, 

 like Professor William James's division of mankind 



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