The twenty tallest crossed plants here average 48.74, and the twenty tallest self-fertilised 35.2 inches in height; or as 100 to 72.  These plants after being measured were cut down close to the ground, and the twenty crossed plants weighed 195.75 ounces, and the twenty self-fertilised plants 123.25 ounces; or as 100 to 63.

In Tables 6/88, 6/89 and 6/90, we have the measurements of fifty-six plants derived from two plants of the third self-fertilised generation crossed with pollen from a fresh stock, and of fifty-six plants of the fourth self-fertilised generation derived from the same two plants.  These crossed and self-fertilised plants were treated in three different ways, having been put, firstly, into moderately close competition with one another in pots; secondly, having been subjected to unfavourable conditions and to very severe competition from being greatly crowded in two large pots; and thirdly, having been sown separately in open and good ground, so as not to suffer from any mutual competition.  In all these cases the crossed plants in each lot were greatly superior to the self-fertilised.  This was shown in several ways,—­by the earlier germination of the crossed seeds, by the more rapid growth of the seedlings whilst quite young, by the earlier flowering of the mature plants, as well as by the greater height which they ultimately attained.  The superiority of the crossed plants was shown still more plainly when the two lots were weighed; the weight of the crossed plants to that of the self-fertilised in the two crowded pots being as 100 to 37.  Better evidence could hardly be desired of the immense advantage derived from a cross with a fresh stock.

26.  Primulaceae.—­Cyclamen persicum. (6/5.  Cyclamen repandum according to Lecoq ‘Geographie Botanique de l’Europe’ tome 8 1858 page 150, is proterandrous, and this I believe to be the case with Cyclamen persicum.)

Ten flowers crossed with pollen from plants known to be distinct seedlings, yielded nine capsules, containing on an average 34.2 seeds, with a maximum of seventy-seven in one.  Ten flowers self-fertilised yielded eight capsules, containing on an average only 13.1 seeds, with a maximum of twenty-five in one.  This gives a ratio of 100 to 38 for the average number of seeds per capsule for the crossed and self-fertilised flowers.  The flowers hang downwards, and as the stigmas stand close beneath the anthers, it might have been expected that pollen would have fallen on them, and that they would have been spontaneously self-fertilised; but these covered-up plants did not produce a single capsule.  On some other occasions uncovered plants in the same greenhouse produced plenty of capsules, and I suppose that the flowers had been visited by bees, which could hardly fail to carry pollen from plant to plant.