228 THE HISTORY OF CREATION. 
that organic individuals experience transformations and 
assume forms in consequence of changes of nutrition which 
have not operated on them themselves, but upon their 
parental organism. The transforming influence of the 
external conditions of existence, of climate, of nutrition, 
etc., shows its effects here not directly in the transform- 
ation of the organism itself, but indirectly in that of its 
descendants. (Gen. Morph. ii. 202.) 
As the principal and most universal of the laws of in- 
direct variation must be mentioned the law of indi- 
vidual adaptation, or the important proposition that all 
organic individuals from the commencement of their indi- 
vidual existence are unequal, although often very much 
alike. Asa proof of this proposition, I may at once point 
to the fact, that in the human race in general all brothers 
and sisters, all children of the same parents, are unequal 
from their birth. No one will venture to assert that two 
children at their birth are perfectly alike: that the size of 
the individual parts of their bodies, the number of hairs on 
their heads, the number of cells composing their outer skins 
or epidermis, the number of blood-cells are the same in both 
children, or that hoth children have come into the world 
with the same abilities or talents. But what more specially 
proves this law of individual difference, is the fact that in 
_the case of those animals which produce several young ones 
at a time,—for instance, dogs and cats,—all the young of 
each birth differ from one another more or less strikingly 
in size and colour of the individual parts of the body, or 
in strength, etc. Now this law is universal. All organic 
individuals from their beginning are distinguished by cer- 
tain, though often extremely minute, differences, and the 
