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garden, (when my seeds originally came) having a different soil and aspect. from my garden. The on flowers on the self-fertilised plants of the last or second generation (Tab. 29) were also allowed to fertilise themselves spontaneouslyunder the net, and yielded plenty of seeds. These latter and the crossed seeds after germinating on sand, were planted in equal pairs on the opposite sides of six large pots, which were kept at first in a cool greenhouse. Early in January their heights were measured to the tips of their leaves. The thirteen crossed plants averaged 13.16 inches in height, and the twelve (for one had died) self-fertilised plants averaged 13.7 inches; or as 100 to 104. So that the taller self-fertilised plants exceeded by a little the crossed plants.

Early in the spring the plants were gradually hardened off and turned out of their pots into the open ground without being disturbed. By the end of August the greater number had formed fine heads;

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but several grew extremely crooked, from having been drawn up to the light whilst in the greenhouse. As it was scarcely possible to measure their heights, the finest plant on each side of each pot was cut down close to the ground and weighted. In the following Table we have the result.

Table 30.

Cabbages Weight of whole plants after they had formed heads.

 

The six finest crossed plants thus average

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108.16 oz, whilst the six finest self-fertilised plants average only 23.7 oz.; or as 100 to 22. This difference shows in the clearest manner the enormous benefit which was these plants derived from a cross with another a plant of belonging the same sub-variety, but of to a fresh stock and grown during at least the three last previous generations under somewhat different conditions.

The effects of crossing offspring from, a cut-leaved, curled and variegated white-green cabbage crossed with a cut-leaved curled and variegated crimson-green cabbage, in comparison ed with the self-fertilised offspring from the same two varieties. self-fertilised. These trials were made, not for the sake of comparing the growth of the curled crossed and self-fertilised seedlings, but because I had seen it stated that they would not naturally intercross when growing uncovered and near each one another. This statement proved quite erroneous; but I found that the white-green variety was proved in my garden in some degree sterile; producing little pollen

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and few seeds. It was therefore no wonder that seedlings raised from its artificially the self-fertilised flowers of this variety were greatly exceeded in height by seedlings raised from a cross with between it & the more vigorous crimson-green variety; and nothing more need to be said about this experiment.

The seedlings from the the reciprocal cross, ─ that is, from the crimson-green variety fertilised with pollen from by the white-green variety offered a somewhat more cu curious case. A few of these crossed seedlings reverted to a pure green variety with their leaves less cut and curled, so that they were altogether in a much more natural state; and these plants grew more vigorously and taller than any of the others.

Now it is a strange fact that a much larger number of the self-fertilised seedlings from the crimson-green variety thus reverted than of the crossed seedlings, and as a consequence the self-fertilised seedlings ultimately grew taller by an average of 2 1/2 inches