1 862.] OF FLOWERS. 275 



length), and the proboscis of a moth sufficiently long to reach 

 the nectar, might be developed by natural selection. He goes 

 on to point out that on any other theory we must suppose 

 that the flower was created with an enormously long nectary, 

 and that then by a special act, an insect was created fitted to 

 visit the flower, which would otherwise remain sterile. With re- 

 gard to this point my father wrote (October 12 or 13, 1867) : — 



" I forgot to remark how capitally you turn the tables on 

 the Duke, when you make him create the Angrsecum and 

 Moth by special creation." 



If we examine the literature relating to the fertilisation of 

 flowers, we do not find that this new branch of study showed 

 any great activity immediately after the publication of the 

 Orchid-book. There are a few papers by Asa Gray, in 1862 

 and 1863, by Hildebrand in 1864, and by Moggridge in 1865, 

 but the great mass of work by Axell, Delpino, Hildebrand, 

 and the Miillers, did not begin to appear until about 1867. 

 The period during which the new views were being assimi- 

 lated, and before they became thoroughly fruitful, was, how- 

 ever, surprisingly short. The later activity in this depart- 

 ment may be roughly gauged by the fact that the valuable 

 ' Bibliography,' given by Prof. D'Arcy Thompson in his 

 translation of Muller's ' Befruchtung ' (1883), contains refer- 

 ences to 814 papers. 



Besides the book on Orchids, my father wrote two or three 

 papers on the subject, which will be found mentioned in the 

 Appendix. The earliest of these, on the three sexual forms 

 of Catasetum, was published in 1862 ; it is an anticipation 

 of part of the Orchid-book, and was merely published in the 

 Linnean Society's Journal, in acknowledgment of the use 

 made of a specimen in the Society's possession. The possi- 

 bility of apparently distinct species being merely sexual forms 

 of a single species, suggested a characteristic experiment, 

 which is alluded to in the following letter to one of his earliest 

 disciples in the study of the fertilisation of flowers :] 



T 2 



