Breeding and the Mendelian discovery / by A.D. Darbishire ... with illustrations in colour and black-and-white.

  • Arthur Dukinfield Darbishire
Date:
1911
Catalogue details

Licence: Attribution-NonCommercial 4.0 International (CC BY-NC 4.0)

Credit: Breeding and the Mendelian discovery / by A.D. Darbishire ... with illustrations in colour and black-and-white. Source: Wellcome Collection.

    173/370 page 107
    CHARACTERS OF DISTINCT PAIRS 107 namely presence of rose and absence of pea ; the green wrinkled has two recessive characters, so has the single —absence of both pea and rose. And the proportions in which these analogous things occur in the second hybrid generation are the same, thus :— 9 Walnut 3 Pea. 3 Rose. 1 Single. [= Pea and [= absence of both Rose ] Pea and Rose ] 9 Yellow round, 3 yellow wrinkled, 3 green round, 1 green wrinkled- It will be remembered that it was said earlier in this chapter that the same results would have followed if, instead of crossing a yellow wrinkled with a green round pea, a yellow round were crossed with a green wrinkled. The two crosses only difíer in the fact that in the former each parent has a dominant character, whilst in the latter both dominant characters exist in one parent. The cross we have described in the case of the fowl's comb, namely pea by rose, is analogous to the one displayed in Plate III., namely, yellow wrinkled by green round. In both cases each parent has a dominant character. The cross in the case of the combs, analogous to that between yellow round and green wrinkled, is a cross between walnut (possessing, or consisting of, two dominant characters, pea and rose ) and single. Here, as in the case of the peas, precisely the same results follow in the second hybrid generation, namely 9 walnut, 3 rose, 3 pea, and 1 single. The appearance, in the
    digitised image 1
    digitised image 2
    digitised image 3