“Mr. Hewitt possessed an excellent Sebright gold-lace bantam hen, which, as she became old, grew diseased in her ovaria and assumed male characters. In this breed the males resemble the females in all respects except in their combs, wattles, spurs, and instincts; hence it might have been expected that the diseased hen would have assumed only those masculine characters which are proper to the breed, but she acquired, in addition, well-arched tail sickle-feathers quite a foot in length, saddle-feathers on the loins, and hackles on the neck--ornaments which, as Mr. Hewitt remarks, would be held to be abominable in this breed.” This is the only record I know of showing the change that takes place in the Sebright hen when the influence of her ovary is removed. There can be no doubt from the above description that she changes in the same way as does the castrated Sebright male. Concerning the origin of the Sebright bantam Darwin states that the race “originated about the year 1800 from a cross between a common bantam and a Polish fowl, recrossed by a hen-tailed bantam, and carefully selected; hence there can hardly be a doubt that the sickle feathers and hackles which appeared in the old hen were derived from the Polish fowl or common bantam; and we thus see that not only certain masculine characters proper to the Sebright bantam, but other masculine characters derived from the first progenitors of the breed, removed by a period of about 60 years, were lying latent in this hen bird ready to be evolved as soon as her ovaria became diseased.” To-day the problem appears to us in a somewhat different light, since the secondary sexual characters referred to by Darwin have simply been kept under for more than a hundred years by the secretion produced in the ovary of the hen (as in all breeds) and in the testis of the male Sebright. HEREDITY OF HEN-FEATHERING. In 1913 I found that hen-feathering as seen in the Sebright is a dominant non-sex-linked character. A preliminary statement was given in the first edition of my book on Heredity and Sex (1913), which treated the character as a recessive one. This was a mistake due to a male having been obtained that was like the game race, which subsequent work showed must have been due to a sperm having been retained in the oviduct of the female during her isolation period. In the second edition published a few months later the mistake, having been found out, was corrected. If _one_ dominant suffices to produce hen-feathering, the F₂ ratio would be 3 hen-feathered to 1 cock-feathered bird. The numbers found were 31 to 28. This realized ratio departs too far from a 3:1 ratio to make it probable that the results are due to a single factor.