Fertilisation of Orchids - Further Research By Darwin

Further Research By Darwin

Darwin had "found the study of orchids eminently useful in showing me how nearly all parts of the flower are coadapted for fertilisation by insects, & therefore the result of n. selection,—even most trifling details of structure". His own interest in orchids and in fertilisation of plants by insects continued. Darwin had been given the use of a hot-house at The Rookery on the other side of the village, and at the end of 1862 he was persuaded by this neighbour's helpful gardener to have his own built at Down House as an extension to the existing cold lean-to greenhouse. The gardener drew up plans, and Darwin investigated stoves and ventilation devices. When it was completed in February 1863 he asked Hooker for some plants from Kew Gardens, writing "I long to stock it, just like a school-boy", and sent his butler with a cart. When over 160 different plants were delivered, Darwin made apologetic remarks about depleting the national collection. He told Hooker "You cannot imagine what pleasure your plants give me ... Henrietta & I go & gloat over them." Darwin's life was changed by having a warm hothouse to spend time in before his walk round the Sandwalk, and in the 1870s he had several more hothouses built. The children later remembered this routine and the gardeners attending to Darwin's experimental plants, as well as the way that Darwin used simple equipment for his experiments, dissecting and measuring plants and seeds.

A chance observation "thoroughly aroused" Darwin's attention to a surprising decrease in vigour of the offspring of Linaria vulgaris following only one instance of self-fertilisation, and after eleven years of experimental work he published The Effects of Cross and Self Fertilisation in the Vegetable Kingdom in 1876 as "a complement to the 'Fertilisation of Orchids,' because it shows how important are the results of cross-fertilisation which are ensured by the mechanisms described in that book." He told a friend "I cannot endure doing nothing", and resumed his work on orchids, assisted in his research by his son Francis Darwin. He corresponded about orchids with Fritz Müller, and almost completely rewrote the book with a considerable amount of new material, much of which was contributed by Müller. The revised edition was published in 1877.

Francis Darwin described it as characteristic that his father delighted in the observations that preceded the publication of Fertilisation of Orchids, not the applause which followed it. He quoted one of his father's last letters about orchids, written in 1880:

They are wonderful creatures, these Orchids, and I sometimes think with a glow of pleasure, when I remember making out some little point in their method of fertilisation.