broccoli, a Brussels sprout, and a Sugar-loaf cabbage near together and left them uncovered.  Seeds collected from each kind were sown in separate beds; and the majority of the seedlings in all five beds were mongrelised in the most complicated manner, some taking more after one variety, and some after another.  The effects of the Kohl-rabi were particularly plain in the enlarged stems of many of the seedlings.  Altogether 233 plants were raised, of which 155 were mongrelised in the plainest manner, and of the remaining 78 not half were absolutely pure.  I repeated the experiment by planting near together two varieties of cabbage with purple-green and white-green lacinated leaves; and of the 325 seedlings raised from the purple-green variety, 165 had white-green and 160 purple-green leaves.  Of the 466 seedlings raised from the white-green variety, 220 had purple-green and 246 white-green leaves.  These cases show how largely pollen from a neighbouring variety of the cabbage effaces the action of the plant’s own pollen.  We should bear in mind that pollen must be carried by the bees from flower to flower on the same large branching stem much more abundantly than from plant to plant; and in the case of plants the flowers of which are in some degree dichogamous, those on the same stem would be of different ages, and would thus be as ready for mutual fertilisation as the flowers on distinct plants, were it not for the prepotency of pollen from another variety. (10/36.  A writer in the ‘Gardeners’ Chronicle’ 1855 page 730, says that he planted a bed of turnips (Brassica rapa) and of rape (B. napus) close together, and sowed the seeds of the former.  The result was that scarcely one seedling was true to its kind, and several closely resembled rape.)

Several varieties of the radish (Raphanus sativus), which is moderately self-fertile when insects are excluded, were in flower at the same time in my garden.  Seed was collected from one of them, and out of twenty-two seedlings thus raised only twelve were true to their kind. (10/37.  Duhamel as quoted by Godron ‘De l’Espece’ tome 2 page 50, makes an analogous statement with respect to this plant.)

The onion produces a large number of flowers, all crowded together into a large globular head, each flower having six stamens; so that the stigmas receive plenty of pollen from their own and the adjoining anthers.  Consequently the plant is fairly self-fertile when protected from insects.  A blood-red, silver, globe and Spanish onion were planted near together; and seedlings were raised from each kind in four separate beds.  In all the beds mongrels of various kinds were numerous, except amongst the ten seedlings from the blood-red onion, which included only two.  Altogether forty-six seedlings were raised, of which thirty-one had been plainly crossed.