Mendelism / by R.C. Punnett.

  • Reginald Crundall Punnett
Date:
1912
Catalogue details

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

Credit: Mendelism / by R.C. Punnett. Source: Wellcome Collection.

    38/218 page 16
    MENDELISM CHAP. characters in which the various races of peas differ from one another. In planning his crossing experiments Mendel adopted an attitude which marked him off sharply from the earlier hybridisers. He realised that their failure to elucidate any general principle of heredity from the results of cross fertilisation was due to their not having concentrated upon particular characters or traced them carefully through a sequence of generations. That source of failure he was careful to avoid, and throughout his ex¬ periments he crossed plants presenting sharply contrasted characters, and devoted his efforts to observing the behaviour of these characters in successive generations. Thus in one series of ex¬ periments he concentrated his attention on the * transmission of the characters tallness and dwarf- ness, neglecting in so far as these experiments were concerned any other characters in which the parent plants might differ from one another. For this purpose he chose two strains of peas, one of about 6 feet in height, and another of about feet. Previous testing had shown that each strain bred true to its peculiar height. These two strains were artificially crossed ^ with one another, and it was found to make no difference which was used as the pollen parent and which was used as the ovule parent. In either case the result was the same. The result of crossing tall with dwarf was in every case nothing but talis, as tall or even a little taller than the tall parent. For this reason Mendel termed tallness the dominant and dwarfness the 1 Cf. note on p. 171.
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