st evidence in favour of it. We _must_ assume it, _because no
other possibility of explanation is open to us, and because these
adaptations actually exist, that is to say, have really taken place_.
With this conviction I attempted, as far back as 1894, when the idea
of germinal selection had not yet occurred to me, to make "harmonious
adaptation" (coadaptation) more easily intelligible in some way or
other, and so I was led to the idea, which was subsequently expounded
in detail by Baldwin, and Lloyd Morgan, and also by Osborn, and Gulick
as _Organic Selection_. It seemed to me that it was not necessary that
all the germinal variations required for secondary variations should
have occurred _simultaneously_, since, for instance, in the case of
the stag, the bones, muscles, sinews, and nerves would be incited by
the increasing heaviness of the antlers to greater activity in _the
individual life_, and so would be strengthened. The antlers can only
have increased in size by very slow degrees, so that the muscles and
bones may have been able to keep pace with their growth in the
individual life, until the requisite germinal variations presented
themselves. In this way a disharmony between the increasing weight of
the antlers and the parts which support and move them would be
avoided, since time would be given for the appropriate germinal
variations to occur, and so to set agoing the _hereditary_ variation
of the muscles, sinews and bones.[42]

I still regard this idea as correct, but I attribute less importance
to "organic selection" than I did at that time, in so far that I do
not believe that it _alone_ could effect complex harmonious
adaptations. Germinal selection now seems to me to play the chief part
in bringing about such adaptations. Something the same is true of the
principle I have called _Panmixia_. As I became more and more
convinced, in the course of years, that the _Lamarckian principle_
ought not to be called in to explain the dwindling of disused parts, I
believed that this process might be simply explained as due to the
cessation of the conservative effect of natural selection. I said to
myself that, from the moment in which a part ceases to be of use,
natural selection withdraws its hand from it, and then it must
inevitably fall from the height of its adaptiveness, because inferior
variants would have as good a chance of persisting as better ones,
since all grades of fitness of the part in question would be