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Chapter 7

last generation

(3) Brassica oleracea. Some flowers plants of the second generation self-fertilised were crossed by with pollen from a plant of the same variety of the cabbage, brought from a distant garden; and they other flowers were again self-fertilised. From each their seeds plants crossed by the fresh stock and plants of the third self-fertilised generation were raised. The former was were to the latter self-fertilized in weight as 100 to 22; which & this is an enormous influence due to a difference,─the result of the beneficial effects of a cross with by a fresh stock, and so of the deteriorating effects of self- fertilization continued during three generations.

(4) Iberis umbellata.—Seedlings from a crimson English variety crossed by a pale-coloured variety which had been grown for some generations in Algiers, were in height to the self-fertilised seedlings from the crimson variety as 100 to 89, and in fertility as 100 to 75.

I am surprised that this cross with another variety did not produce a still more strongly marked beneficial effect; for some intercrossed plants of the crimson English variety put into competition with plants of the same variety self-fertilised from during three generations, were in height as 100 to 86, and in fertility as 100 to 75. The slightly greater difference in height in this latter case, may possibly be attributed to the deteriorating effects of self