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the phenomena of the past presented to us； the convenient epochs and
formations of the geologist； though having a certain distinctness； would
fade into one another with limits as undefinable as those of the
distinct and yet separable colours of the solar spectrum。
Such is a brief summary of the main truths which have been established
concerning species。 Are these truths ultimate and irresolvable facts；
or are their complexities and perplexities the mere expressions of a
higher law？
A large number of persons practically assume the former position to be
correct。 They believe that the writer of the Pentateuch was empowered
and commissioned to teach us scientific as well as other truth； that
the account we find there of the creation of living things is simply
and literally correct； and that anything which seems to contradict it
is； by the nature of the case； false。 All the phenomena which have
been detailed are； on this view； the immediate product of a creative
fiat and consequently are out of the domain of science altogether。
Whether this view prove ultimately to be true or false； it is； at any
rate； not at present supported by what is commonly regarded as logical
proof； even if it be capable of discussion by reason； and hence we
consider ourselves at liberty to pass it by； and to turn to those views
which profess to rest on a scientific basis only； and therefore admit of
being argued to their consequences。 And we do this with the less
hesitation as it so happens that those persons who are practically
conversant with the facts of the case （plainly a considerable advantage）
have always thought fit to range themselves under the latter category。
The majority of these competent persons have up to the present time
maintained two positions；the first； that every species is； within
certain defined or definable limits； fixed and incapable of
modification； the second； that every species was originally produced by
a distinct creative act。 The second position is obviously incapable of
proof or disproof； the direct operations of the Creator not being
subjects of science； and it must therefore be regarded as a corollary
from the first； the truth or falsehood of which is a matter of evidence。
Most persons imagine that the arguments in favour of it are
overwhelming； but to some few minds； and these； it must be confessed；
intellects of no small power and grasp of knowledge； they have not
brought conviction。 Among these minds； that of the famous naturalist
Lamarck； who possessed a greater acquaintance with the lower forms of
life than any man of his day； Cuvier not excepted； and was a good
botanist to boot； occupies a prominent place。
Two facts appear to have strongly affected the course of thought of this
remarkable manthe one； that finer or stronger links of affinity
connect all living beings with one another； and that thus the highest
creature grades by multitudinous steps into the lowest； the other； that
an organ may be developed in particular directions by exerting itself
in particular ways； and that modifications once induced may be
transmitted and become hereditary。 Putting these facts together；
Lamarck endeavoured to account for the first by the operation of the
second。 Place an animal in new circumstances； says he； and its needs
will be altered； the new needs will create new desires； and the attempt
to gratify such desires will result in an appropriate modification of
the organs exerted。 Make a man a blacksmith； and his brachial muscles
will develop in accordance with the demands made upon them； and in like
manner； says Lamarck； 〃the efforts of some short…necked bird to catch
fish without wetting himself have； with time and perseverance； given
rise to all our herons and long…necked waders。〃
The Lamarckian hypothesis has long since been justly condemned； and it
is the established practice for every tyro to raise his heel against
the carcass of the dead lion。 But it is rarely either wise or
instructive to treat even the errors of a really great man with mere
ridicule； and in the present case the logical form of the doctrine
stands on a very different footing from its substance。
If species have really arisen by the operation of natural conditions； we
ought to be able to find those conditions now at work； we ought to be
able to discover in nature some power adequate to modify any given kind
of animal or plant in such a manner as to give rise to another kind；
which would be admitted by naturalists as a distinct species。 Lamarck
imagined that he had discovered this 'vera causa' in the admitted facts
that some organs may be modified by exercise； and that modifications；
once produced； are capable of hereditary transmission。 It does not
seem to have occurred to him to inquire whether there is any reason to
believe that there are any limits to the amount of modification
producible； or to ask how long an animal is likely to endeavour to
gratify an impossible desire。 The bird； in our example； would surely
have renounced fish dinners long before it had produced the least effect
on leg or neck。
Since Lamarck's time； almost all competent naturalists have left
speculations on the origin of species to such dreamers as the author of
the 'Vestiges'； by whose well…intentioned efforts the Lamarckian theory
received its final condemnation in the minds of all sound thinkers。
Notwithstanding this silence； however； the transmutation theory； as it
has been called； has been a 〃skeleton in the closet〃 to many an honest
zoologist and botanist who had a soul above the mere naming of dried
plants and skins。 Surely； has such an one thought； nature is a mighty
and consistent whole； and the providential order established in the
world of life must； if we could only see it rightly； be consistent with
that dominant over the multiform shapes of brute matter。 But what is
the history of astronomy； of all the branches of physics； of chemistry；
of medicine； but a narration of the steps by which the human mind has
been compelled； often sorely against its will； to recognize the
operation of secondary causes in events where ignorance beheld an
immediate intervention of a higher power？ And when we know that living
things are formed of the same elements as the inorganic world； that they
act and react upon it； bound by a thousand ties of natural piety； is it
probable； nay is it possible； that they； and they alone； should have no
order in their seeming disorder； no unity in their seeming
multiplicity； should suffer no explanation by the discovery of some
central and sublime law of mutual connexion？
Questions of this kind have assuredly often arisen； but it might have
been long before they received such expression as would have commanded
the respect and attention of the scientific world； had it not been for
the publication of the work which prompted this article。 Its author；
Mr。 Darwin； inheritor of a once celebrated name； won his spurs in
science when most of those now distinguished were young men； and has
for the last 20 years held a place in the front ranks of British
philosophers。 After a circumnavigatory voyage； undertaken solely for
the love of hi