Bateson proceeds to consider colour-blindness as though its heredity were of similar kind. He refers to it as a male character latent in the female, remarks that we should expect that disease or removal of the ovaries might lead to the occasional appearance of colour-blindness in females. He also discusses the case of _Abraxas grossulariata_ and its variety _lacticolor_, and other cases of sex-linked heredity, apparently with the idea that all such cases are similar to those of sexual dimorphism. _A. lacticolor_ occurs in nature only in the female sex, and when bred with _grossulariata_ [male] produces [male]'s and [female]'s all _grossulariata_, these of course being heterozygous. When the _F1 grossulariata_ [male] was bred with the wild _lacticolor_ [female] it produced both forms in both sexes, and thus _lacticolor_ [male] was obtained for the first time. When this _lacticolor_ [male] was bred with _F1 grossulariata_[female] it produced all the [male]'s _grossulariata_ and all the [female]'s _lacticolor_. Bateson's explanation is that the female, according to the Mendelian theory of sex, is heterozygous in sex, the male homozygous and recessive, and that _lacticolor_ is linked with the female sex-character, _grossulariata_ being repelled by that character. Thus we have, the _lacticolor_ character being recessive, lact. male, LL male male x F, gross. female, GL female male Gametes L male + L male x G male + L female _____________________|______________________ | | GL male male LL male female gross. male lact. female It will be seen that although in the progeny of this mating all the _grossulariata_ were males and all the _lacticolor_ females, yet this case is by no means similar to that of sexual dimorphism in which the characters are normally always confined to the same sex. For the _lacticolor_ character in the parent was in the male, while in the offspring it was in the female. We cannot say here that in the theoretical factors which are supposed to represent what happens, the _lacticolor_ character is coupled with the female sex-factor, for we find it with the male sex-character in the _lacticolor_ [male]. It is so coupled only in the heterozygous _grossulariata_ [female], and at the same time the _grossulariata_ character is repelled.