albino GAMETES, germs, that is to say, which are destitute
of the pigment-forming factor, may have been originally produced by
individuals standing an indefinite number of generations back in the
ancestry of the actual albino, and it is indeed almost certain that the
variation to which the appearance of the albino is due cannot have taken
place in a generation later than that of the grandparents. It is true
that when a new DOMINANT appears we should feel greater confidence
that we were witnessing the original variation, but such events are
of extreme rarity, and no such case has come under the notice of an
experimenter in modern times, as far as I am aware. That they must have
appeared is clear enough. Nothing corresponding to the Brown-breasted
Game fowl is known wild, yet that colour is a most definite dominant,
and at some moment since Gallus bankiva was domesticated, the element on
which that special colour depends must have at least once been formed in
the germ-cell of a fowl; but we need harder evidence than any which has
yet been produced before we can declare that this novelty came through
over-feeding, or change of climate, or any other disturbance consequent
on domestication. When we reflect on the intricacies of genetic problems
as we must now conceive them there come moments when we feel almost
thankful that the Mendelian principles were unknown to Darwin. The time
called for a bold pronouncement, and he made it, to our lasting profit
and delight. With fuller knowledge we pass once more into a period of
cautious expectation and reserve.

In every arduous enterprise it is pleasanter to look back at
difficulties overcome than forward to those which still seem
insurmountable, but in the next stage there is nothing to be gained by
disguising the fact that the attributes of living things are not what
we used to suppose. If they are more complex in the sense that the
properties they display are throughout so regular (I have in view, for
example, the marvellous and specific phenomena of regeneration,
and those discovered by the students of "Entwicklungsmechanik". The
circumstances of its occurrence here preclude any suggestion that this
regularity has been brought about by the workings of Selection. The
attempts thus to represent the phenomena have resulted in mere parodies
of scientific reasoning.) that the Selection of minute random variations
is an unacceptable account of the origin of their diversity, yet by
v