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ce of the principle in works of high antiquity。 In rude and barbarous periods of English history choice animals were often imported； and laws were passed to prevent their exportation： the destruction of horses under a certain size was ordered； and this may be compared to the 'roguing' of plants by nurserymen。 The principle of selection I find distinctly given in an ancient Chinese encyclopaedia。 Explicit rules are laid down by some of the Roman classical writers。 From passages in Genesis； it is clear that the colour of domestic animals was at that early period attended to。 Savages now sometimes cross their dogs with wild canine animals； to improve the breed； and they formerly did so； as is attested by passages in Pliny。 The savages in South Africa match their draught cattle by colour； as do some of the Esquimaux their teams of dogs。 Livingstone shows how much good domestic breeds are valued by the negroes of the interior of Africa who have not associated with Europeans。 Some of these facts do not show actual selection； but they show that the breeding of domestic animals was carefully attended to in ancient times； and is now attended to by the lowest savages。 It would； indeed； have been a strange fact； had attention not been paid to breeding； for the inheritance of good and bad qualities is so obvious。
At the present time； eminent breeders try by methodical selection； with a distinct object in view； to make a new strain or sub…breed； superior to anything existing in the country。 But； for our purpose； a kind of Selection； which may be called Unconscious； and which results from every one trying to possess and breed from the best individual animals； is more important。 Thus； a man who intends keeping pointers naturally tries to get as good dogs as he can； and afterwards breeds from his own best dogs； but he has no wish or expectation of permanently altering the breed。 Nevertheless I cannot doubt that this process； continued during centuries； would improve and modify any breed； in the same way as Bakewell； Collins； &c。； by this very same process； only carried on more methodically； did greatly modify； even during their own lifetimes； the forms and qualities of their cattle。 Slow and insensible changes of this kind could never be recognised unless actual measurements or careful drawings of the breeds in question had been made long ago； which might serve for comparison。 In some cases； however； unchanged or but little changed individuals of the same breed may be found in less civilised districts； where the breed has been less improved。 There is reason to believe that King Charles's spaniel has been unconsciously modified to a large extent since the time of that monarch。 Some highly competent authorities are convinced that the setter is directly derived from the spaniel； and has probably been slowly altered from it。 It is known that the English pointer has been greatly changed within the last century； and in this case the change has； it is believed； been chiefly effected by crosses with the fox…hound； but what concerns us is； that the change has been effected unconsciously and gradually； and yet so effectually； that； though the old Spanish pointer certainly came from Spain； Mr Barrow has not seen； as I am informed by him； any native dog in Spain like our pointer。
By a similar process of selection； and by careful training； the whole body of English racehorses have come to surpass in fleetness and size the parent Arab stock； so 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 differ 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 have produced the result which 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 barbarians 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 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 a 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； I cannot doubt； 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； thus slowly and unc