38 Nature of the Formative Stimulus 
can reach the organ by any other way and indeed by a 
way quite the opposite of the normal as happens for 
example in any distribution of electric or hydrodynamic 
energy, and that consequently it amounts to the same 
thing whether the regeneration of the tissue or of the 
organ ablated proceeds in the same way as in ontogeny 
or by any other way. 
And finally we must suppose that regeneration is 
nothing else than a particular case of generation or 
reproduction and that the nature of one is substantially 
identical with that of the other: for, to use the words 
of Delage “generation is only the regeneration of a 
complete organism by a portion of greater or less size 
attached to it or detached from it;”’ 44 so the causes of 
the regeneration, for instance of a little disc of skin 
which has been removed, must be essentially the same 
as those which effect a complete reproduction. 
Between the two phenomena the following difference 
will however exist: The regeneration of a little disc 
of skin will be due, according to what we have just stated, 
to the fact that the continuous nervous flux which flows 
through the whole organism and particularly through 
those parts which were contiguous with the part removed, 
would tend to reestablish its dynamic equilibrium, dis- 
turbed by the operation. If we accept the fundamental 
biogenetic law in its first degree of approximation, 
complete generation, on the contrary, would be a whole 
series of transitions of the nervous energy circulating or 
distributed in the developing organism, from one dynamic 
system to the other next in order, both meanwhile being 
in a state of equilibrium since they were already formerly 
14Delage: L’hérédité et les grands problémes de la biologie 
générale. P. o8. 
