500 ANNALS NEW YORK ACADEMY OF SCIENCES 



versing the tissue. This lower limit is, on the average, 82 per cent of 

 the computed total charge. It seems unlikely that the external charge 

 is, actually, much nearer than this to the total charge. From these 

 considerations, we should judge it improbable that our assumptions 

 involve a systematic error, whereby the actual values of the energy 

 should be consistently more than about 15 per cent lower than those 

 found by the method we have used. 



The question as to how much the actual values may exceed those we 

 find, presents a greater uncertainty. Although, as was just explained, 

 it is difficult to propose an equivalent network for the electric organs 

 which will dissipate much less energy than we allow for in internal 

 currents, there is no difficulty in proposing a network to dissipate more 

 energy. This follows from Thevenin's theorem of electric networks, 

 according to which any electromotive force inferred from external 

 measurements may be regarded, alternatively, as the open-circuit volt- 

 age of a concealed network containing a higher electromotive force. 

 On the other hand, our calculations ascribe to the single electroplax 

 layer an electromotive force about as high as any that are found at 

 boundaries in bioelectric phenomena. This suggests that the actual 

 values of the electrical quantities are not very much greater than those 

 we calculate. For the energy, which is the most uncertain of these 

 quantities, twice the calculated value appears to be a safe upper limit. 



REFERENCES 



1. Gotch, F. 



1900. The Physiology of Electrical Organs. Textbook of Physiology, Vol. 2. 

 Young J. Pentland, Edinburgh and London; MacMillan, New York. 

 (This article contains references to a number of original sources.) 



2. Cox, R. T., & C. M. Breder, Jr. 



1943. Observations on the electric discharge of Narcine brasiliensis (Olfers). 

 Zoologica 28: 45. 



3. Cox, R. T., W. A. Rosenblith, J. A. Cutler, R. S. Mathews, & C. W. Coates 



1940. A comparison of some electrical and anatomical characteristics of the 

 electric eel, Electrophorus electricus (Linnaeus). Zoologica 25: 553. 



4. Cox, R. T., C. W. Coates, & M. V. Brown 



1945 Relations between the structure, electrical characteristics, and chemical 

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5. Coates, C. W., & R. T. Cox 



1945. A comparison of length and voltage in the electric eel, Electrophorus 

 electricus (Linnaeus). Zoologica. 30: 89. 



6. Coates, C. W., & R. T. Cox 



1942. 01)servations on the electric discharge of Torpedo occidentalis. Zoologica. 

 27:25. 



7. Nachmansohn, D., R. T. Cox, C. W. Coates, & A. L. Machado 



1943. Action potential and enzyme activity in the electric organ oi Electrophorus 

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