Page:Darwin - The various contrivances by which orchids are fertilized by insects (1877).djvu/75

. II. From what I had then seen of other Orchids, I was so much surprised at the self-fertilisation of this species, that I examined during many years, and asked others to examine, the state of the pollen-masses in many hundreds of flowers, collected in various parts of England. The particulars are not worth detailing; but I may give as an instance, that Mr. Farrer found in Surrey that not one flower out of 106 had lost both pollinia, and that only three had lost a single one. In the Isle of Wight, Mr. More examined 136 flowers, and of these the very unusual number of ten had lost both, and fourteen had lost one; but then he found that in eleven cases the caudicles had been gnawed through apparently by snails, the discs still remaining in their pouches; so that the pollinia had not been carried away by insects. In some few cases, also, in which I found the pollinia removed, the petals were marked with the slime of snails. Nor must we forget that a blow from a passing animal, and possibly heavy storms of wind might occasionally cause the loss of one or both pollinia.

During most years the pollen-masses of the many hundred flowers which were examined, adhered with the rarest exceptions to the stigma, with their discs still enclosed within the pouches. But in the year 1868, from some cause the nature of which I cannot conjecture, out of 116 flowers gathered in two localities in Kent, seventy-five retained both pollinia in their cells; ten had one pollinium, and only thirty-one had both adhering to the stigma. Long and often as I have watched plants of the Bee Ophrys, I have never seen one visited by any insect. Robert Brown imagined