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that the latter, by the regulations for the Goodwood Races, are favoured in the weights they carry. Lord Spencer and others have shown how the cattle of England have increased in weight and in early maturity, compared with the stock formerly kept in this country. By comparing the accounts given in old pigeon treatises of carriers and tumblers with these breeds as now existing in Britain, India, and Persia, we can, I think, clearly trace the stages through which they have insensibly passed, and come to di er so greatly from the rock-pigeon.

Youatt gives an excellent illustration of the effects of a course of selection, which may be considered as unconsciously followed, in so far that the breeders could never have expected or even have wished to produce the result whic_ ensued—namely, the production of two distinct strains. The two flocks of Leicester sheep kept by Mr. Buckley and Mr. Burgess, as Mr. Youatt remarks, “ have been purely bred from the original stock of Mr. Bakewell for upwards of fifty years. There is not a suspicion existing in the mind of any one at all acquainted with the subject that the owner of either of them has deviated in any one instance from the pure blood of Mr. Bakewell’s flock, and yet the difference between the sheep possessed by these two gentlemen is so great that they have the appearance of being quite different varieties.”

If there exist savages so barbarous as never to think of the inherited character of the offspring of their domestic animals, yet any one animal particularly useful to them, for any special purpose, would be carefully preserved during famines and other accidents, to which savages are so liable, and such choice animals would thus generally leave more offspring than the inferior ones; so that in this case there would be a kind of unconscious selection going on. We see the value set on animals even by the barbanans of Tierra del Fuego, by their killing and devouring their old women, in times of dearth, as of less value than their dogs.

In plants the same gradual process of improvement, through the occasional preservation of the best individuals, whether or not sufficiently distinct to be ranked at their first appearance as distinct varieties, and whether or not two or more species or races have become blended together by crossing, may plainly be recognised in the increased size and beauty which we now see in the varieties of the heartsease, rose, pelargonium, dahlia, and

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other plants, when compared with the older varieties or with their parent-stocks. No one would ever expect to get a first-rate heartsease or dahlia from the seed of a wild plant. No one would expect to raise a first-rate melting pear from the seed of the wild pear, though he might succeed from a poor seedling growing wild, if it had come from a garden-stock. The pear, though cultivated in classical times, appears, from Pliny’s description, to have been a fruit of very inferior quality. I have seen great surprise expressed in horticultural works at the wonderful skill of gardeners, in having produced such splendid results from such poor materials; but the art has been simple, and, as far as the final result is concerned, has been followed almost unconsciously. It has consisted in always cultivating the best known variety, sowing its seeds, and, when a slightly better variety has chanced to appear, selecting it, and so onwards. But the gardeners of the classical period, who cultivated the best pear they could procure, never thought what splendid fruit we should eat; though we owe our excellent fruit, in some small degree, to their having naturally chosen and preserved the best varieties they could anywhere find.

%A large amount of change in our cultivated plants, t us slowly and unconsciously accumulated, explains, as I believe, the well-known fact, that in a vast number of cases we cannot recognise, and therefore do not know, the wild parent-stocks of the plants which have been longest cultivated in our flower and kitchen gardens. If it has taken centuries or thousands of years to improve or modify most of our plants up to their present standard of usefulness to man, we can understand how it is that neither Australia, the Cape of Good Hope, nor any other region inhabited by quite uncivilised man, has afforded us a single plant worth culture; It is not that these countries, so rich in species, do not by a strange chance possess the aboriginal stocks of any useful plants, but that the native plants have not been improved by continued selection up to a standard of perfection comparable with that giVen to the plants in countries anciently

c‘ ilised.

Gr; regard to the domestic animals kept by uncivilised man, it should not be overlooked that they almost always have to struggle for their own food, at least during certain seasons. j And in two countries very dif

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44 VARIATION UNDER DOMESTICATION

ferently circumstanced, individuals of the same species, having slightly different constitutions or structure, would often succeed better in the one country than in the other ; and thus by a process of “natural selection,” as will hereafter be more fully explained, two sub-breeds might be formed. This, perhaps, partly explains what 'has been remarked by some authors, namely, that Lthe varieties kept by savages have more of the character of species than the varieties kept in civilised countries; COn the view here given of the all-important part which selection by man has played, it becomes at once obvious, how it is that our domestic races show adaptation in their _ structure or in their habits to man’s wants or fanciesf"; We can, I think, further understand the frequently abnormal character of our domestic races, and likewise their differences being so great in external characters "and relatively so slight in internal parts or organs. Z Man can hardly select, or only with much difficulty, any \deviation of structure excepting such as is externally visible Dand indeed he rarely cares for what is internal. He cannever act by seflectioinL'exceptinglLvariations which are firstgivefi ~tthim in some slight degremby nature. No manwould ever tryt6 make‘ a fantail, till he saw a pigeon with a tail developed in some slight degree in an unusual manner, or a pouter till he saw a pigeon with a crop of somewhat unusual size; and the more abnormal or unusual any character was when it first appeared, the 'more likely it would be to catch his attention. But to use such an expression as trying to make a fantail, is, I have no doubt, in most cases, utterly in— correct. The man who first selected a pigeon with a slightly larger tail, never dreamed what the descendants of that pigeon would become through long-continued, partly unconscious and partly methodical selection. Perhaps the parent-bird of all fantails had only fourteen tail-feathers somewhat expanded, like the present Java fantail, or like individuals of other and distinct breeds, in which as many as seventeen tail-feathers have been counted. Perhaps the first pouter-pigeon did not inflate its crop much more than the turbit now does the upper part of its oesophagus—a habit which is disregarded by all fanciers, as it is not one of the points of the breed. Nor let it be thought that some great deviation of structure would be necessary to catch the fancier’s eye: he perceives extremely small differences, and it is in

human nature to value any novelty, however slight, in one’s own possession. Nor must the value which would formerly be set on any slight differences in the individuals

of the same species, be judged of by the value which would now be set on them, after several breeds have once fairly been established. Many slight differences might, and indeed do now, arise amongst pigeons, which are rejected as faults or deviations from the standard of perfection of each breed. The common goose has not given rise to any marked varieties; hence the Toulouse and the common breed, which differ only in colour, that most fleeting of characters, have lately been exhibited as distinct at our poultry-shows. 4,, LI think these views further explain what has sometimesbeen noticed—namely, that we know nothing about the origin or history of any of our domestic breeds. But,_i;r fact, a breed, likeha dialect of a language, can ardly berth said tobave had a definite origin. A man preserves and?“ breeds from'an individual with some slight deviation of structure, or takes more care than usual in matching his best animals and thus improves them, and the improved individuals slowly spread in the immediate neighbourhood. But as yet they will hardly have a distinct name, and from being only slightly valued, their history will be disregarded. When further improved by the same slow and gradual process, they will spread more widely, and will get recognised as something distinct and valuable, and will then probably first receive a provincial name. In semi-civilised countries, with little free communication, the spreading and knowledge of any new sub-breed would be a slow process. As soon as the points of value of the new sub-breed are once fully acknowledged, the principle, as I have called it, of unconscious selection will always tend,-—perhaps more at one period than at another, as the breed rises or falls in fashion,—perhaps more in one district than in another, according to the state of civilisation of the inhabitants,—slowly to add to the characteristic features of the breed, whatever they may be. But the chance will be infinitely small of any record having been preserved of such slow, varying, and insensible changes.

I_must/now say a few words on the cgegmstanees, favourable, or thg_1'everse, to man’s power of selection. A high degree of variability is obviously'Ifavourable,“as freely giving the materials for selection to work on; not

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that mere individual differences are not amply sufficient,
with extreme care, to allow of the accumulation of a
large amount of modification in almost any desired
direction. But as variations manifestly useful or pleasing
to man appear only occasionally, the chance of their
appearance will be much increased by a large number of
individuals being kept; and hence this comes to be of
the highest importance to success. On this principle
Marshall has remarked, with respect to the sheep of parts
of Yorkshire, that “ as_they generally belong to poor
peeple, and are mostly in small lots, they never can be
improved.” On the other hand, nurserymen, from raising
large stocks of the same plants, are generally far more
successful than amateurs in getting new and valuable
varieties. The keeping of a large number of individuals
of a species in any country requires that the species
should be placed under favourable conditions of life, so
as to breed freely in that country. [When the individuals
of any species are scanty, all the individuals, whatever
their quality may be, will generally be allpwed to breed,
and this will effectually prevent selection.,J But probably ' '
the most important point of all is that the animal or
plant should be so highly useful to man, or so much valued
by him, that the closest attention should be paid to even
the slightest deviation in the qualities or structure of
each individual. Unless such attention be paid nothing
can be effected. ~I have seen it gravely remarked, that
it was most fortunate that the strawberry began to
vary just when gardeners began to attend closely to this
plant. [No doubt the strawberry had always varied since
it was cultivated, but the slight varieties had been neg-
lected. As soon, however, as gardeners picked out
individual plants, with slightly larger, earlier, or better
fruit, and raised seedlings from them, and again picked
out the best seedlings and bred from them, then, there
appeared (aided by some crossing with distinct species)
those many admirable varieties of the strawberry which
have been raised during the last thirty or forty yearsf

In the case of animals with separate sexes, facility in preventing crosses is an important element of success in the formation of new races,—at least, in a country which is already stocked with other races. In this resp ect enclosure of the land plays a part. Wandering savages or the inhabitants of open plains rarely possess more than one breed of the same species. Pigeons can be

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