Page:Mendel's principles of heredity; a defence.pdf/97

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in Hybridisation
77

12 feet high, and yellow coloured pods, constricted when ripe. The ratios of the numbers in which the different forms appeared in the separate generations were the same as with Pisum. Also the development of the constant combinations resulted according to the law of simple combination of characters, exactly as in the case of Pisum. There were obtained—

Constant
combinations
Axis Colour of
the unripe pods.
Form of
the ripe pods.
1 long green inflated
2 constricted
3 yellow inflated
4 constricted
5 short green inflated
6 constricted
7 yellow inflated
8 constricted

The green colour of the pod, the inflated forms, and the long axis were, as in Pisum, dominant characters.

Another experiment with two very different species of Phaseolus had only a partial result. Phaseolus nanus, L., served as seed parent, a perfectly constant species, with white flowers in short racemes and small white seeds in straight, inflated, smooth pods; as pollen parent was used Ph. multiflorus, W., with tall winding stem, purple-red flowers in very long racemes, rough, sickle-shaped crooked pods, and large seeds which bore black flecks and splashes on a peach-blood-red ground.

The hybrids had the greatest similarity to the pollen parent, but the flowers appeared less intensely coloured. Their fertility was very limited; from seventeen plants, which together developed many hundreds of flowers, only forty-nine seeds in all were obtained. These were of