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plant in the greenhouse produced a good many grains.

Canna warscewiczi (Marantaceae).--Highly self-fertile.

Orchidaceae.--In Europe Ophrys apifera is as regularly self-fertilised as is any cleistogene flower. In the United States, South Africa, and Australia there are a few species which are perfectly self-fertile. These several cases are given in the second edition of my work on the Fertilisation of Orchids.

Allium cepa (blood red var.) (Liliaceae).--Four flower-heads were covered with a net, and they produced somewhat fewer and smaller capsules than those on the uncovered heads. The capsules were counted on one uncovered head, and were 289 in number; whilst those on a fine head from under the net were only 199.]

Each of these lists contains by a mere accident the same number of genera, namely, forty-nine. The genera in the first list include sixty-five species, and those in the second sixty species; the Orchideae in both being excluded. If the genera in this latter order, as well as in the Asclepiadae and Apocynaceae, had been included, the number of species which are sterile if insects are excluded would have been greatly increased; but the lists are confined to species which were actually experimented on. The results can be considered as only approximately accurate, for fertility is so variable a character, that each species ought to have been tried many times. The above number of species, namely, 125, is as nothing to the host of living plants; but the mere fact of more than half of them being sterile within the specified degree, when insects are excluded, is a striking one; for whenever pollen has to be carried from the anthers to the stigma in order to ensure full fertility, there is at least a good chance of cross-fertilisation. I do not, however, believe that if all known plants were tried in the same manner, half would be found to be sterile within the specified limits; for many flowers were selected for experiment which presented some remarkable structure; and such flowers o

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