542 The American Naturalist. [July, 
reached a view which considers ontogenetic selection an im- 
portant factor in development. Without prejudicing the state- 
ment of fact at all we may enquire into the actual working of 
the organism is making its organic selections or adaptations. 
The question is simply this: how does the organism secure, 
from the multitude of possible ontogenetic changes which it 
might and does undergo, those which are adaptive? As a 
matter of fact, all personal growth, all motor acquisitions made 
by the individual, show that it succeeds in doing this; the 
further question is, how? Before taking this up, I must repeat 
with emphasis that the position taken in the foregoing pages, 
which simply makes the fact of ontogenetic adaptation a factor 
in development, is not involved in the solution of the further 
question as to how the adaptations are secured. But from the 
answer to this latter question we may get further light of the 
interpretation of the facts themselves. So we come to ask how 
Organic Selection actually operates in the case of a particular 
adaptation of a particular creature (ref. 1; ref. 2, chap. vii, 
xili; ref. 6, and 7). 
I hold that the organism has a way of doing this which is 
- peculiarly its own. The point is elaborated at such great 
length in the book referred to (ref. 2) that I need not repeat 
details here. The summary in this journal (ref. 6) may have 
been seen by its readers. There is a fact of physiology which, 
taken together with the facts of psychology, serves to indicate 
the method of the adaptations or accommodations of the in- 
dividual organism. The general fact is that the organism 
concentrates it energies upon the locality stimulated, for the 
continuation of the conditions, movements, stimulations which 
are vitally beneficial, and for the cessation of the conditions, 
movements, stimulations, which are vitally depressing and 
harmful. In the case of beneficial conditions we find a general 
increase of movement, an excess discharge of the energies of move- 
ment in the channels already open and habitual; and with this, 
on the psychological side, pleasurable consciousness and attention. 
Attention to a member is accompanied by increased vaso- 
motor activity, with higher muscular power, and a general 
dynamogenic heightening in that member. “The thought of a 
