No. 420.] REGENERATION IN THE EGG. 957 
and, hence, the essential condition is absent. Our conception 
of the structure of a magnet must be also fundamentally dif- 
ferent from the ideas involved in the organization of the egg. 
It is true that any piece of a magnet at once becomes a whole 
magnet of smaller size, and this occurs in the smallest pieces 
that it is possible to obtain. On the other hand, the change 
in the organization of a piece of the egg is a relatively slow 
one, and it can take place only in a relatively large piece of the 
substance. If it be objected that these differences are only 
trivial ones, and not essential, still it can be shown, I think, 
that we must hold entirely different views of the nature of the 
polarity of a magnet and the organization of the egg. Our 
conception of the polarity of the magnet rests on the idea that 
itis the sum total of the polarities, or, perhaps, of the orien- 
tation of the minutest elements, the molecules, of which the 
magnet is made up, while our conception of the organization 
of the egg is exactly the reverse (or at least I shall try to 
show that we must really believe this to be the case), and we 
must think of the entire egg as a whole and not the sum total 
of an infinite number of smaller wholes. We may claim, I 
think, that this property of the egg substance of forming itself 
into a new whole is peculiar to the living protoplasm and is a 
property that we do not find, or have not found as yet, 1n inor- 
ganic, or perhaps we may go further and say in dead, matter. 
If we choose to call this property of living matter à vital factor 
in the sense that it is not found in matter that is dead there 
can be, I think, little objection to so doing. If the statement 
seems to be arguing in a circle, we may state more simply that 
those properties of living things that are not shown by non- 
living things we shall call vital properties. We may add that 
we cannot be sure, at present, whether these vital factors will 
conflict with our present ideas of causality or not ; they seem 
rather to be, however, new causal phenomena peculiar to dé 
tain organic substances or compounds, but it would be Qut, o 
place here to examine further into these difficult questions. 
I have dwelt somewhat at length on this topic because, 
as I shall try to show, an analysis of the phenomenon m 
takes place when a piece of an adult animal (hydra, tor 
