In the case where both parents are F2 or F3 it is impossible to summate results, since the gametic formulæ of the different parents are so diverse; but the same types of solid blacks, black with trace of red in the males, Game-colored males and females, and Game with red replaced by white repeatedly occur. My plan of increasing red in the Dark Brahmas met with wholly unexpectedly prompt success, but not in the way anticipated. The result was not due to selection, but to the recombination of the factors necessary to make the Game plumage coloration.
(2) Production of a buff race by selection.—The second test was directed toward the production de novo of a new buff race from a Game fowl.
As is well known, all of our red and "buff" races, like the Buff Leghorn, Rhode Island Red, and others, have been derived from the Buff Cochin that came to us from China. The fact that a buff bird has, so far as I have been able to learn, not been produced in western countries indicates the probability that it can not be so produced at will; but the attempt seemed worth while.
I began with a Black Breasted Red Game because its plumage color is that of the primitive ancestor of domesticated poultry, and on that hypothesis the ancestor of the buff races. If these buff races were produced by extending the red through selection of the reddest offspring, that should be possible now as in the past.
A start in the direction of creating a buff bird would seem to require the elimination of the black. By crossing a black and red Game with a White Leghorn I got, in 1905, 2 white pullets with red on breast and some black specks. By crossing a Game Bantam (wingless) with a White Leghorn I got white birds with red present on wing-bar of male and breast of females and also some black spots.
In 1906 I mated 2 of these white (+ red) bantam hybrid hens with a hybrid cock and obtained again red on the wing-coverts of some white hybrids, while some were without red. From one of the hens I got 4 offspring, or 20 per cent of all, with buff on hackle-lacing, breast, and wing-coverts.
In 1907 I mated a prevailingly white male of the preceding year, that had red wing-bar, hackle, and breast, with the reddest females and obtained, along with pure whites and blacks and barred birds, these colors combined with red in various degrees, but not clearly in advance of the reddest of 1906. In 1908 I mated a white male, having red as in the Game, with my reddest hybrids. Again, white and white-and-buff birds appeared, but they showed no advance, except in one instance, among 138 young. This individual (No. 7950), derived exclusively from the Black-red Game and White Leghorn on one side and on the other from the White Leghorn-Game Bantam cross, had a uniform buff down. Unfortunately the chick quickly died.
The conclusion is that after three years of selection of the reddest offspring no appreciable increase of the red was observed—except for the remarkable case of one undeveloped chick with completely buff down. This, indeed, looks like a sport, or, perhaps, it is due to unsuspected factors. The experiment will be continued.
F. NON-INHERITABLE CHARACTERS.
So well-nigh universal is heredity that it is justifiable to entertain a doubt whether any character may fail of inheritance. So far as my experience goes, non-inheritable characters are such as are weak in ontogeny, so that they may readily fail of development even when conditions are propitious; or else they are so complex—so far removed from simple unit-characters—that their heritability in accordance with established canons is obscured. The first case is apparently illustrated by the rumpless cock (No. 117) and the wingless fowl; the second case by lop-comb and by right-and-left alternatives in general.