422 THE GARDENER. [Sept. 



instructive paper on "Natural and Artificial Hybridisation." He 

 introduced his subject by noticing the minute and intricate nature 

 of the processes by which the reproduction of plants are effected, 

 and proceeded to give a description of the various parts of a flower, 

 pointing out those more immediately connected with the produc- 

 tion of seed, — some of the most common modes by which fertil- 

 isation is effected being by agencies in some instances within, in 

 others beyond, the flower. The wind and insects are the principal 

 agents in this operation when the flower is not adapted for self-fertili- 

 sation, and ob.servation shows how perfect are the means for accom- 

 plishing this object. When there is no gaily coloured flowers to allure 

 insects, the pollen is light and powdery, and wind is commonly the 

 means of transfer; but when flowers have bright-coloured corollas, 

 there is also, in most cases, honey to induce the visits of insects, or at 

 any rate pollen as food for the young of the domestic bee, and the 

 pollen is of a gummy nature. Insects in quest of food carry off some 

 of the pollen-grains, and in their visits to other flowers deposit at least 

 a part of these grains on the stigma. In addition to that class of 

 plants which are unable to fertilise themselves in consequence of the 

 sexual organs being on different plants, or at least in different flowers, 

 there are others in which the sexual organs, though together, are not 

 matured or sufficiently developed at the same time. Sometimes the 

 stigma is in a ripe or receptive state long before the stamens are fully 

 developed ; while in other cases, the anthers shed the pollen-grains 

 before the stigma is in a state to receive them. An example of this 

 latter arrangement is to be seen in the Campanula family, where the 

 pollen is not only shed, but in some cases the anthers are completely 

 withered away before the stigma is fully developed. On the other hand, 

 the Plantain or Ribgrass furnishes an example where the stigma has 

 become developed and decayed before the stamens make their appear- 

 ance on the same flower. The examples referred to will indicate that 

 nature has made ample provision for cross-fertilisation, and that in 

 the vegetable as well as in the animal world close breeding is pro- 

 vided against. 



Mr NicoU then spoke of the amazing number of the pollen-grains, 

 and their great variety of form in different species. When pollen from 

 the same flower, or different flowers on the same plant, or even from a 

 different plant of the same species, is deposited on the stigma, and fer- 

 tilisation follows, no change need be looked for in the future progeny 

 from seed thus fertilised, further than may be produced by cultivation, 

 change of soil, climate, or other extraneous conditions — in short, no 

 hybrid form will result. It was only in cases of cross-fertilisation be- 

 tween two distinct species that a new form might be looked for. But 

 even though no improvement, or even alteration, were to result, cross- 

 fertilisation might be of great value in regard to the extra production 

 of seed. 



