270 Theories Treating of Inheritance 
the living substances characteristic of their species. We 
are able in this way to present even a mathematical defini- 
tion of the personality of a given individual of a species, 
to a certain extent an arithmetical personal description 
of this individual, namely the list of co-efficients of the 
mixture of his specific substances.” 2°4 
The proportions of this mixture persist unaltered in 
all cells of the same organism. Upon this mixture 
depends the quality of the chemical reactions, i. e. of the 
molecular movements; upon these latter again depend 
the molar movements or osmotic currents of nutritive and 
excretive material; upon the molar movement finally 
depends the form of each plastid as well as that of the 
most complicated organism: 
“Tt is absolutely useless to suppose, in the egg which 
produces man, other characters present than for example 
those of a simple hepatic or epithelial assimilative ele- 
ment, determining by this assimilation the molar move- 
ments around it. These molar movements associated 
with the movements which result from assimilation in 
neighboring elements, and also with the existence of the 
skeleton such as is constituted in a thenceforth unchange- 
able form from the moment of its first anlage, determine 
the conditions of local equilibrium from which the local 
form of the body results. Analogously as soon as a 
human element (the fecundated egg) is capable of liv- 
ing by itself alone, the molar movements, which assimila- 
tion provokes first in this element alone and later in all 
which are derived from it, determine the successive 
forms of the growing mass arising from assimilation. 
The phenomenon appears from the outside then to be 
24 Le Dantec: Ibid. P. 267. 
