OP PISHES. 31 



ment with untiring speed, and devour their help- 

 less victims, when practicable, at a single mouth- 

 ful. 



It will be perceived, therefore, that this remark- 

 able difference in organization, adapts these two 

 families, to that peculiar condition of things, exist- 

 ing in the element in which they were designed to 

 live. 



" Eat or be eaten" is the only law known to 

 the inhabitants of the ocean. Each individual, 

 therefore, under the instinctive influence of that 

 immutable ordinance, feeds luxuriously on its 

 nearest neighbor ; and, at last, from the insecurity 

 of its home, is preyed upon in its turn. 



Another law, no less important and interesting 

 in its operation, explains that prolific attribute, 

 which is characteristic of this race of beings. Sus- 

 tained on food already animalized, its rapid assim- 

 ilation soon perfects the growth ; and were it not 

 for incessant slaughter throughout the seas, the 

 ocean could not contain its own. The putrid ex- 

 halations of the floating dead, if this eternal war- 

 fare for food were suspended, would corrupt the 

 atmosphere of the whole globe, and all life would 

 inevitably be sacrificed to the over-peopling of the 

 world of waters.* 



* Most fishes seem to give a preference to living food : it 

 is only under the influence of extreme hunger, that they are 



