362 Monpho genetic Factors 



electrical potential differences in trees, as related to the phenomena of 

 polarity, dominance, and correlation in them. 



If bioelectrical fields are actually concerned with the specific character 

 of development, it would seem possible to change them by applying 

 other electrical fields externally and thus perhaps to modify organic 

 form. This turns out to be very difficult to accomplish, however. Never- 

 theless, Lund ( 1945 ) was able to inhibit completely the growth in length 

 of an onion root by passing an electric current upward through it, al- 

 though the same current passing downward produced little or no inhi- 

 bition. 



It is tempting to explain all form differences as results of these constant 

 bioelectric fields, and they may well be concerned with the control 

 of organic development. Such fields are doubtless related to the fine 

 structure of protoplasm and the complex pattern of surfaces which this 

 presents. Whether the fields are the cause of developmental changes or 

 are themselves the result of chemical or physical factors is an important 

 theoretical question. The problem of bioelectric factors is too complex for 

 easy solution, but it should certainly continue to be attacked vigorously 

 by those who are qualified to do so. 



The volume by Lund and his collaborators ( 1947 ) presents a good ac- 

 count of the problem of bioelectrical fields and their implications for 

 morphogenesis. Rosene has gathered for it a bibliography of 1,406 titles. 



