122 E. G. SPAULDING. 



Between the difficulties of the two views it seems necessary 

 to conclude that certain ions penetrate the membrane because of 

 their and its specific chemical nature and of their greater com- 

 parative velocity and notwithstanding the possible repulsion, and 

 that there follows a specific chemical effect on the chemically 

 organized cell contents accompanied by those electrical and 

 osmotic phenomena above considered. That there is a chemical 

 effect is indicated also by the different results obtained in deter- 

 mining the rhythm of immunity of fertilized Arbacia eggs to 

 ether, HC1, KC1, etc., an account of which will appear in a later 

 paper. Furthermore, from this standpoint there should be in 

 theory no effect resulting from the use of either the anodal or 

 kathodal end of the current on the eggs of, e. g., Aster ias, and 

 the negative results of such experiments carried on by the author 

 this summer are confirmatory of this view. 



CONCLUSIONS AND SUMMARY. 



Under the experimentally justified assumption that the organ- 

 ism is a peculiar complex of energies, so that general physical 

 principles are therefore valid for it, it is found that the effective- 

 ness of both normal and artificial fertilization methods can be 

 explained from one standpoint, viz., firstly, that the necessary 

 condition for the event of cleavage, is the creation, previous to 

 it, of an uncompensated potential difference between osmotic 

 pressure and surface tension by increasing in a chemically or- 

 ganized egg either absolutely or relatively the pressure or by 

 decreasing the surface tension ; secondly, that the event of 

 cleaving is itself identical with the equilibrating and compensat- 

 ing of this difference, which necessiates an average decrease in 

 both the potentials, osmotic pressure, and surface tension ; and 

 thirdly, that there is an accompanying unequal distribution of 

 electrical charges at the surface and at the center in such a way 

 that constriction results therefrom. 



This constitutes the synthesis which we purposed, and is 

 offered only as an attempt, that, although in itself justifiable, pre- 

 sents much that is incomplete and tentative. 



COLLEGE OF THE CITY OF NEW YORK, 



DEPARTMENT OF PHILOSOPHY, December 22, 1903. 



