No. 420.] REGENERATION IN THE EGG. 973 
In the first part of this paper I have given my reasons for 
looking upon the organization of living things as a phenome- 
non sui generis, and I have wished to bring here into connec- 
tion with this consideration the conception of polarity as 
applied to the organism. It is a phenomenon, I think, that 
is different from the one bearing the same name applied to 
inorganic substances. We are therefore, I think, justified in 
looking upon the reorganization of pieces of the egg, embryo, 
and adult as a phenomenon peculiar to the living structure of 
'the egg, and without a parallel in inorganic nature. It seems 
to be one of the peculiar physical properties connected with 
the matter that we call living substance, and in the last analysis 
we find it to be not simply the outcome of a complex of known 
physical principles. We are therefore, I believe, also justified 
in calling the organization of living things a vital property in 
the sense, to repeat what I have just said, that it is peculiar to 
this kind of substance or structure, and not the result of a 
complex of known physical principles ; or, in other words, it is a 
physical phenomenon as fundamental as the polarity shown by 
crystals or the magnetism of the magnet, and just as the latter 
are associated with certain kinds of matter, so is the organiza- 
tion associated with the substance protoplasm. 
