Chap. II.
OPHRYS MUSCIFERA.
45
CHAPTER II.
OPHREÆ—continued.
Fly and Spider Ophrys—Bee Ophrys, apparently adapted for perpetual self-fertilisation, but with paradoxical contrivances for intercrossing—Herminium monorchis, attachment of the pollinia to the front legs of insects—Peristylus viridis, fertilisation indirectly effected by nectar secreted from three parts of the labellum—Gymnadenia conopsea, and other species—Habenaria or Platanthera chlorantha and bifolia, their pollinia attached to the eyes of Lepidoptera—Other species of Habenaria—Bonatea—Disa—Summary on the powers of movement in the pollinia.
The genus Ophrys differs from Orchis chiefly in having separate pouch-formed rostella,[1] instead of the two being confluent.
In Ophrys muscifera, or the Fly Ophrys, the chief peculiarity is that the caudicle of the pollinium (B, fig. 5) is doubly bent. The nearly circular piece of membrane, to the under side of which the ball of viscid matter adheres, is of considerable size, and forms the summit of the rostellum. It is thus freely exposed
- ↑ It is not correct to speak of two rostella, but the inaccuracy may be forgiven from its convenience. The rostellum strictly is a single organ, formed by the modification of the dorsal stigma and pistil; so that in Ophrys the two pouches, the two viscid discs, and the space between them together form the true rostellum. Again, in Orchis I have spoken of the pouch-formed organ as the rostellum, but strictly the rostellum includes the little crest or fold of membrane (see B in fig. 1) projecting, between the bases of the anther-cells. This folded crest (sometimes, converted into a solid ridge) corresponds with the smooth surface lying between the two pouches in Ophrys, and owes its protuberant and folded condition in Orchis to the two pouches having been brought together and rendered confluent. This modification will be more fully explained in a future chapter.
