ELECTRIC FISH 



series is a convenience for the mind, which takes into 

 account only the degrees of this special capacity. There 

 is actually no such relation in Nature. 



The conclusion at which we arrive is that we are 

 confronted with distinct and concrete cases, identical as 

 regards structure and function, different as regards 

 powers and distribution, with the added circumstance 

 that they are found only in fishes. We have answered 

 the question " How? " but can we answer the question 

 "Why ? " At what door must we knock to gain 

 some light upon their origin, the cause or causes which 

 have brought them into being in the living world? 

 What influence has been exercised over the muscles 

 which act mechanically, to convert them into electric 

 batteries? In short, whence does all this come? 



The answers are plain. There can be no question 

 of formation or progress by usage. There is too 

 much of a jump from a normal muscle to even a rudi- 

 mentary electric organ, and the distribution is not 

 wide enough. Nor is their presence in the fishes that 

 possess them due to affinity. Their occurrence is an 

 example of a condition which, though potentially it 

 can exist anywhere, is realized and found only in a 

 few creatures. Doubtless, by reason of their dual 

 electrical and mechanical power, all striated muscles 

 possess the latent capacity to become electrogenic. 

 But only a few of them have succeeded in realizing 

 this. 



Life, as it continually progresses up the scale, is 

 devoted to two actions which are both simultaneous 

 and mutually dependent. One, in the matter which 

 it animates, unceasingly creates possibilities of structure, 

 tissues, organs, and individuals. The other brings 

 these possibilities into touch with environment, which 

 provides the substance and energy which permit some 

 to realize themselves and help towards their support, 

 while holding up others and preventing them from 

 getting any further, simply by refusing to support 

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