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Show 40 SELECTION BY M.A.N. CHAP. J. most fleeting of characters, have lately been exhibited as distinct at our poultry-shows. . I think these views further explain what ~as sometimes been noti.c e d- name1 y , that we know .n othmg aboBu t th· e ori ·nor history of any of our domestic breeds. ut, In facf, a breed, like a dialect of a language, can hardly be ·a t h e had a definite origin. A man preserves and sa1 o av · h d · t• f br ee ds f rom an individual with some shg· t eviha. Ionh o. t t e Or takes more care than usual In mate 1ng IS s rue ur , d h · d b t ·mals and thus improves them, an t e Improve · eas · a·an i a· . hb ls slowly spread in the imme Iate neig OUr- Ill IVI ua di . hood. But as yet they will hardly have a . sti:nct nam.e, and from being only slightly valued, therr history will be disregarded. When further improved by the .same slow and gradual process, they wil~ spre~d. more widely, and will get recognised as something di~tlnct and .va~uable and will then probably first receive a provincial nam.'e. In semi-civilised countries, with little free communication, the spreading and knowledge of an~ new sub-breed will 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 p~riod than at another as the breed rises or falls In fashion, -perhaps more i~ 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 sma~ of any record having been preserved of such slow, varymg, and insensible changes. I must now say a few words on the circumstan?es, favourable, or the reverse, to man's power of selectwn. A high degree of variability is obviously favourable, as freely giving the materials for selection to work on· not that mere individual differences are not amply ' CHAP. I. CIRCUMSTANCES FAVOURABLE TO SELECTION. 41 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 importanr.e to success. On this principle Marshall has remarked, with respect to the sheep of parts of Yorkshire, that " as they generally belong to poor people, and are mostly in small lots, they never can be improved." On the other hand, nurseryn1en, 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 allowed to breed, and this will effectually prevent selection. 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 neglected. 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 |