[page] 85

The Fertilisation of Winter-flowering Plants

WILL you permit me to add a few words to Mr. Bennett's letter,¹ published at p. 58 of your last number? I did not cover up the Lamium with a bell-glass, but with what is called by ladies, "net." During the last twenty years I have followed this plan, and have fertilised thousands of flowers thus covered up, but have never perceived that their fertility was in the least injured.² I make this statement in case anyone should be induced to use a bell-glass, which I believe to be injurious from the moisture of the contained air. Nevertheless, I have occasionally placed flowers, which grew high up, within small wide-mouthed bottles, and have obtained good seed from them. With respect to the Vinca, I suppose that Mr. Bennett intended to express that pollen had actually fallen, without the aid of insects, on the stigmatic surface, and had emitted tubes. As far as the mere opening of the anthers in the bud is concerned, I feel convinced from repeated observations that this is a most fallacious indication of self-fertilisation. As Mr. Bennett asks about the fertilisation of Grasses, I may add that Signor Delpino, of Florence, will soon publish some novel and very curious observations on this subject, of which he has given me an account in a letter, and which I am glad to say are far from being opposed to the very general law that distinct individual plants must be occasionally crossed.

CHARLES DARWIN

Down, Beckenham, Kent, Nov. 13

¹ Alfred William Bennett (1833-1902), botanist and publisher; his letter on the fertilisation of winter-flowering plants appeared in Nature 1 (1869): 58. See Correspondence vol. 17, p. 477.

² On the netting Darwin used, see Cross and self fertilisation, pp. 10-11.