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philosophers。 After a circumnavigatory voyage； undertaken solely for
the love of his science； Mr。 Darwin published a series of researches
which at once arrested the attention of naturalists and geologists； his
generalizations have since received ample confirmation； and now command
universal assent； nor is it questionable that they have had the most
important influence on the progress of science。 More recently Mr。
Darwin； with a versatility which is among the rarest of gifts； turned
his attention to a most difficult question of zoology and minute
anatomy； and no living naturalist and anatomist has published a better
monograph than that which resulted from his labours。 Such a man； at
all events； has not entered the sanctuary with unwashed hands； and when
he lays before us the results of 20 years' investigation and reflection
we must listen even though we be disposed to strike。 But； in reading
his work it must be confessed that the attention which might at first
be dutifully； soon becomes willingly； given； so clear is the author's
thought； so outspoken his conviction； so honest and fair the candid
expression of his doubts。 Those who would judge the book must read it；
we shall endeavour only to make its line of argument and its
philosophical position intelligible to the general reader in our own
way。
The Baker…street Bazaar has just been exhibiting its familiar annual
spectacle。 Straight…backed； small…headed； big…barrelled oxen； as
dissimilar from any wild species as can well be imagined； contended for
attention and praise with sheep of half…a…dozen different breeds and
styes of bloated preposterous pigs； no more like a wild boar or sow than
a city alderman is like an ourang…outang。 The cattle show has been；
and perhaps may again be； succeeded by a poultry show； of whose crowing
and clucking prodigies it can only be certainly predicated that they
will be very unlike the aboriginal 'Phasianus gallus'。 If the seeker
after animal anomalies is not satisfied； a turn or two in Seven Dials
will convince him that the breeds of pigeons are quite as extraordinary
and unlike one another and their parent stock； while the Horticultural
Society will provide him with any number of corresponding vegetable
aberrations from nature's types。 He will learn with no little surprise；
too； in the course of his travels； that the proprietors and producers
of these animal and vegetable anomalies regard them as distinct
species； with a firm belief； the strength of which is exactly
proportioned to their ignorance of scientific biology； and which is the
more remarkable as they are all proud of their skill in 'originating'
such 〃species。〃
On careful inquiry it is found that all these； and the many other
artificial breeds or races of animals and plants； have been produced by
one method。 The breederand a skilful one must be a person of much
sagacity and natural or acquired perceptive facultynotes some slight
difference； arising he knows not how； in some individuals of his stock。
If he wish to perpetuate the difference； to form a breed with the
peculiarity in question strongly marked； he selects such male and
female individuals as exhibit the desired character； and breeds from
them。 Their offspring are then carefully examined； and those which
exhibit the peculiarity the most distinctly are selected for breeding；
and this operation is repeated until the desired amount of divergence
from the primitive stock is reached。 It is then found that by
continuing the process of selectionalways breeding； that is； from
well…marked forms； and allowing no impure crosses to interfere；a race
may be formed； the tendency of which to reproduce itself is exceedingly
strong； nor is the limit to the amount of divergence which may be thus
produced known； but one thing is certain； that； if certain breeds of
dogs； or of pigeons； or of horses； were known only in a fossil state；
no naturalist would hesitate in regarding them as distinct species。
But； in all these cases we have 'human interference'。 Without the
breeder there would be no selection； and without the selection no
race。 Before admitting the possibility of natural species having
originated in any similar way； it must be proved that there is in nature
some power which takes the place of man； and performs a selection 'sua
sponte'。 It is the claim of Mr。 Darwin that he professes to have
discovered the existence and the 'modus operandi' of this natural
selection； as he terms it； and； if he be right； the process is perfectly
simple and comprehensible； and irresistibly deducible from very
familiar but well nigh forgotten facts。
Who； for instance； has duly reflected upon all the consequences of the
marvellous struggle for existence which is daily and hourly going on
among living beings？ Not only does every animal live at the expense of
some other animal or plant； but the very plants are at war。 The ground
is full of seeds that cannot rise into seedlings； the seedlings rob one
another of air； light and water； the strongest robber winning the day；
and extinguishing his competitors。 Year after year； the wild animals
with which man never interferes are； on the average； neither more nor
less numerous than they were； and yet we know that the annual produce of
every pair is from one to perhaps a million young；so that it is
mathematically certain that； on the average； as many are killed by
natural causes as are born every year； and those only escape which
happen to be a little better fitted to resist destruction than those
which die。 The individuals of a species are like the crew of a
foundered ship； and none but good swimmers have a chance of reaching
the land。
Such being unquestionably the necessary conditions under which living
creatures exist； Mr。 Darwin discovers in them the instrument of
natural selection。 Suppose that in the midst of this incessant
competition some individuals of a species （A） present accidental
variations which happen to fit them a little better than their fellows
for the struggle in which they are engaged； then the chances are in
favour； not only of these individuals being better nourished than the
others； but of their predominating over their fellows in other ways； and
of having a better chance of leaving offspring； which will of course
tend to reproduce the peculiarities of their parents。 Their offspring
will； by a parity of reasoning； tend to predominate over their
contemporaries； and there being （suppose） no room for more than one
species such as A； the weaker variety will eventually be destroyed by
the new destructive influence which is thrown into the scale； and the
stronger will take its place。 Surrounding conditions remaining
unchanged； the new variety （which we may call B）supposed； for
argument's sake； to be the best adapted for these conditions which can
be got out of the original stockwill remain unchanged； all accidental
deviations from the type becoming at once extinguished； as less fit for
their post than B itself。 The tendency of B to persist will grow with
its persistence through successive generations； and it will acquire all
the characters of a new species。
But； on th