The above three spontaneously self-fertilised capsules produced by the two almost completely self-sterile plants, contained altogether five seeds; and from these I raised in the following year (1871) five plants, which were kept under separate nets.  They grew to an extraordinarily large size, and on August 29th were examined.  At first sight they appeared entirely destitute of capsules; but on carefully searching their many branches, two or three capsules were found on three of the plants, half-a-dozen on the fourth, and about eighteen on the fifth plant.  But all these capsules were small, some being empty; the greater number contained only a single seed, and very rarely more than one.  After this examination the nets were taken off, and the bees immediately carried pollen from one of these almost self-sterile plants to the other, for no other plants grew near.  After a few weeks the ends of the branches on all five plants became covered with capsules, presenting a curious contrast with the lower and naked parts of the same long branches.  These five plants therefore inherited almost exactly the same sexual constitution as their parents; and without doubt a self-sterile race of Mignonette could have been easily established.

Reseda lutea.

Plants of this species were raised from seeds gathered from a group of wild plants growing at no great distance from my garden.  After casually observing that some of these plants were self-sterile, two plants taken by hazard were protected under separate nets.  One of these soon became covered with spontaneously self-fertilised capsules, as numerous as those on the surrounding unprotected plants; so that it was evidently quite self-fertile.  The other plant was partially self-sterile, producing very few capsules, many of which were of small size.  When, however, this plant had grown tall, the uppermost branches became pressed against the net and grew crooked, and in this position the bees were able to suck the flowers through the meshes, and brought pollen to them from the neighbouring plants.  These branches then became loaded with capsules; the other and lower branches remaining almost bare.  The sexual constitution of this species is therefore similar to that of Reseda odorata.

Concluding remarks on self-sterile plants.

In order to favour as far as possible the self-fertilisation of some of the foregoing plants, all the flowers on Reseda odorata and some of those on the Abutilon were fertilised with pollen from other flowers on the same plant, instead of with their own pollen, and in the case of the Senecio with pollen from other flowers on the same corymb; but this made no difference in the result.  Fritz Muller tried both kinds of self-fertilisation in the case of Bignonia, Tabernaemontana and Abutilon, likewise with no difference in the result.  With Eschscholtzia, however, he found that pollen from other flowers on the same plant was a little