ON EVOLUTION. 289 
that may be raised against it are entitled to grave considera- 
tion; and, certainly, it is no genuine spirit of scientific caution 
that will forbid us to doubt whether they have all been satis- 
factorily answered. ‘To instance one of the most obvious 
objections—although, it may be, not the strongest—given in 
the pedigree of the original man a species of anthropoid ape, 
equal in rank to the highest type now extant; given, there- 
fore, two organic types which were related to one another, 
but separated by an interval of time which, without a moment’s 
hesitation, we may assume to be no small multiple of a thousand 
years, have we not a right to ask, “ Where are the modern 
analogues, where are any of the fossilised specimens, of the 
innumerable intermediate stages of development? ” Lf sine 
respect to its being both continuous and imperceptible, 
Nature’s progress from the homogeneous to the heterogeneous 
may be imagined to resemble the movement of a glacier, how 
are we to account for so enormously wide a crevasse, which, 
be it observed, shows the split to have been complete, alike 
from top to bottom and from side to side? It is not one 
connecting link that we miss between the brute and the man, 
namely, between the most advanced of the lower races of 
animals now existing and that race which towers and rules 
over all—it is not two or three, but thousands or myriads 
or millions. On the insensible development hypothesis, we 
might reasonably expect to find, at any rate, some transitional 
species of creature, of which it would be impossible to say to 
which of the two classes it belonged. In fact, it is not easy 
to imagine how this hypothesis can be adopted without theo- 
retically expunging from organic nature all those boundary- 
lines, and pulling up all those landmarks, which now render 
classification feasible. The breaches of continuity which 
suffice to frustrate any attempt that might be made to track 
in any direction the supposed course of development are too 
numerous, and for the most part too wide, and in too many 
instances intervene between diversities of structure and func- 
tion remote from similarity, and between peculiarities which 
have no appearance of standing in necessary relation to ex- 
ternal conditions, to admit of being adequately accounted for 
by these conditions, and thus of finding the places they require 
in a definite and full-blown scheme of physiological evolution. 
Passing from this objection, I might proceed to ask what 
should induce Nature, in making choice of individuals with 
a view to their survival, to look with a friendly eye upon such 
budding organs, incipient wings for example, as in their un- 
developed forms can have no more than a prospective value, 
and may, without stretch of imagination, be conceived likely 
