Page:Mendel's principles of heredity; a defence.pdf/90

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70
Mendel's Experiments

angular and yellow; the fourth is constant in both recessive characters, so that the seeds are angular and green. In both these experiments there were consequently four sorts of seed to be expected—viz. round and yellow, round and green, angular and yellow, angular and green.

The crop fulfilled these expectations perfectly. There were obtained in the

1st Experiment, 98 exclusively round yellow seeds ;
3rd 94 ;

In the 2nd Experiment, 31 round and yellow, 26 round and green, 27 angular and yellow, 26 angular and green seeds.

In the 4th Experiment, 24 round and yellow, 25 round and green, 22 angular and yellow, 27 angular and green seeds.

A favourable result could now scarcely be doubted; the next generation must afford the final proof. From the seed sown there resulted for the first experiment 90 plants, and for the third 87 plants which fruited: these yielded for the—

1st Exp. 3rd Exp.
20 25 round yellow seeds AB
23 19 round yellow and green seeds ABb
25 22 round and angular yellow seeds AaB
22 21 round and angular green and yellow seeds AaBb

In the second and fourth experiments the round and yellow seeds yielded plants with round and angular yellow and green seeds, AaBb.

From the round green seeds plants resulted with round and angular green seeds, Aab.

The angular yellow seeds gave plants with angular yellow and green seeds, aBb.

From the angular green seeds plants were raised which yielded again only angular and green seeds, ab.