points, whatever they are, rapidly decline, and there is also a more or less gradual but sure return to the primitive wild type, in size and even colour of the plumage. The purest black or white originally, rapidly becomes first marked with, and ultimately changed into, the original red or brown, whilst the other features simultaneously disappear. If, however, the process of artificial selection be carried too far, and with reference _only to one_ prominent point, any breed is almost sure to suffer in the other qualities which have been neglected, and this has been the case with the very breed already mentioned--the white-faced Spanish. We know from old fanciers that this breed was formerly considered hardy, and even in winter rarely failed to afford a constant supply of its unequalled large white eggs. But of late years attention has been so _exclusively_ directed to the 'white-face,' that whilst this feature has been developed and perfected to a degree never before known, the breed has become one of the most delicate of all, and the laying qualities of at least many strains have greatly fallen off. It would be difficult to avoid such evil results if it were not for a valuable compensating principle, which admits of _crossing_. That principle is, that any desired point possessed in perfection by a foreign breed, may be introduced by crossing into a strain it is desired to improve, and every other characteristic of the cross be, by selection, afterwards bred out again. Or one or more of these additional characteristics may be also retained, and thus a _new variety_ be established, as many have been within the last few years." Size may be imparted to the Dorking by crossing it with the Cochin, and the disposition to feather on the legs bred out again by judicious selection; and the constitution may be strengthened by crossing with the Game breed. Game fowls that have deteriorated in size, strength, and fierceness, by a long course of breeding in-and-in, may have all these qualities restored by crossing with the fierce, powerful, and gigantic Malay, and his peculiarities may be afterwards bred out. The size of the eggs of the Hamburg might very probably be increased without decreasing, or with very slightly decreasing, the number of eggs, by crossing with a Houdan cock; and the size would also be increased for the table. The French breeds, Creve-Coeur, Houdan, and La Fleche, gain in size and hardiness by being crossed with the Brahma cock. The cross between a Houdan cock and a Brahma hen "produces," says the "Henwife," "the finest possible chickens for market, but not to breed from. Pure Brahmas and Houdans alone must be kept for that purpose; I have always found the second cross worthless."