[9] Bateson and Punnett (1908, p. 28) recognize three "kinds" of recessive whites--that of the Silkie, that of the Rose-comb bantams, and that of "white birds that have arisen in the course of our experiments." White Cochins have perhaps been one of the ancestors of Rose-comb bantams; Bateson's new white lay recessive in the White Dorking and when mated to the White Silkie throws Game-colored offspring. "_Grays._"--White Leghorns and their derivatives belong to this class. Its gametic formula is: _CJNWx_. This indicates that the race contains the color enzyme, as well as the Jungle pattern and the supermelanic coat. But all of these are rendered invisible by the graying factor _W_. The superxanthic factor is missing. 2. BLACK. The uniform black birds that I have studied are of several sorts. The Black Minorca and White-faced Black Spanish have the gametic formula _CJNwx_. Owing to the absence of the graying factor and the presence of the color factor these appear as pigmented birds, but the supermelanic coat, _N_, obscures the Jungle coloration, so that the bird appears entirely black. Nevertheless the black is not of uniform quality, but just those parts of the feathers of the wing, back, hackle, saddle, and breast that are red in the Jungle fowl are of an iridescent black, while the portion that is not red in the Jungle is of a dead black. The Black Cochin has the gametic formula _CINwx_. This differs from the formula of the Minorca only in this respect: the Jungle pattern is present, but not the pigmentation that is usually associated with it. The Black Game ("Black Devil") that I used in a few experiments seemed to have the same gametic formula as the Minorca, only the supermelanic coat was less dense. 3. BUFF. For this color I used Buff Cochins, the original buff race. The gametic formula of this race proves to be _CjnwX_--the Jungle-fowl pattern being absent. B. EVIDENCE. The evidence for the gametic interpretations of the self-colored fowl is derived from hybridizations. It will now be presented in detail. 1. SILKIE × MINORCA (OR SPANISH). (Plates 3 to 6.) By hypothesis this cross is between _cJnwx_ and _CJNwx_. The first generation should give the zygotic formula _CcJ2Nnw2x2_, or, more simply, _CcJ2Nn_. This formula resembles closely that for the Minorca; but it differs in this important respect, that the coloring factor and the supermelanic factor are both heterozygous, and hence diluted.