Page:Darwin - The various contrivances by which orchids are fertilized by insects (1877).djvu/220

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VANDEÆ.
Chap. VII.

facts, from corroborating the view taken of the function of the antennæ; for as there are no pollinia to eject, an organ adapted to convey the stimulus from the touch of an insect to the rostellum would be useless. I could find no trace of a viscid disc or pedicel, and no doubt they had been lost; for Dr. Crüger says[1] that "the anther of the female flower drops off immediately after the opening of the same, i. e. before the flower has reached perfection as regards colour, size, and smell. The disc does not cohere, or very slightly, to the pollen-masses, but drops off about the same time, with the anther;" leaving behind them the rudimentary pollen-masses.

Instead of a large stigmatic chamber, there is a narrow transverse cleft close beneath the small anther. I was able to insert one of the pollen-masses of the male Catasetum into this cleft, which from having been kept in spirits was lined with coagulated beads of viscid matter, and with utriculi. The utriculi, differently from those in Catasetum, were charged (after having been kept in spirits) with brown matter. The ovarium is longer, thicker near the base, and more plainly furrowed than in Catasetum; the ovule-bearing cords are also much longer, and the ovules more opaque and pulpy, as in all common Orchids. I believe that I saw the opening at the partially inverted end of the testa, with a large projecting nucleus; but as the specimens had been kept many years in spirits and were somewhat altered, I dare not speak positively. From these facts alone it is almost certain that Monachanthus is a female plant; and as already stated. Sir R. Schomburgk and Dr. Crüger have both seen it seeding abundantly. Altogether the flower differs in a most


  1. 'Journ. Linn. Soc. Bot.' vol. viii. 1864, p. 127.