224 THE HISTORY OF CREATION. 
The first series, comprising the phenomena’ of indirect 
(potential) adaptation, has, on the whole, hitherto been 
little attended to, and Darwin has the merit of having 
directed special attention to this series of changes. It is some- 
what difficult to place this subject clearly before the reader ; 
I will endeavour to make it clear hereafter by examples. 
Speaking quite generally, indirect or potential adaptation 
consists in the fact that certain changes in the organism, 
effected by the influence of nutrition (in its widest sense) and 
of the external conditions of existence in general, show them- 
selves not in the individual form of the respective organism, 
but in that of its descendants. Thus, especially in organisms 
propagating themselves in a sexual way, the reproductive 
system, or sexual apparatus, is often influenced by external 
causes (which little affect the rest of the organism), to such a 
degree that its descendants show a complete alteration of 
form. This can be seen very strikingly in artificially pro- 
duced monstrosities. Monstrosities can be produced by sub- 
jecting the parental organism to certain extraordinary con- 
ditions of life, and, curiously enough, such an extraordinary 
condition of life does not produce a change of the organ- 
ism itself, but a change in its descendants. This cannot be 
called transmission by inheritance, because it is not a quality 
existing in the parental organism that is transmitted by 
inheritance. It is, on the contrary, a change affecting the 
parental organism, but not perceptible in it, that appears in 
the peculiar formation of its descendants. It is only the 
impulse to this new formation which is transmitted in pro- 
pagation through the egg of the mother or the sperm of 
the father. The new formation exists in the parental 
organism only as a possibility (potential) ; in the descend- 
ants it becomes a reality (actual). 
