he was surprised at the gigantic seed-vessels of the Monachanthus; and he correctly remarks that "here we have traces of sexual difference in Orchideous flowers." Dr. Crüger also informs me that in Trinidad he never saw capsules naturally produced by the flowers of this Catasetum;[1] nor when they were fertilised by him with their own pollen, as was done repeatedly. On the other hand, when he fertilised the flowers of the Monachanthus viridis with pollen from the Catasetum, the operation never failed. The Monachanthus also commonly produces fruit in a state of nature.
From what I had myself observed, I was led to examine carefully the female organs of C. tridentatum, callosum, and saccatum. In no case was the stigmatic surface viscid, as it is in all other Orchids (except as we shall hereafter see in Cypripedium), and as is indispensable for securing the pollen-masses by the rupture of the caudicles. I carefully looked to this point both in young and old flowers of C. tridentatum. When the surface of the stigmatic chamber and of the stigmatic canal of the above-named three species is scraped off, after having been kept in spirits, it is found to be composed of utriculi (including nuclei of the proper shape), but not nearly so numerous as with ordinary Orchids. The utriculi cohere more together
- ↑ Dr. Hance writes to me that he has in his collection a plant of Catasetum tridentatum from the West Indies bearing a fine capsule; but it does not appear to have been ascertained that this particular flower was that of Catasetum, and there is no great improbability in a single flower of Monachanthus being produced by a plant of Catasetum, as well as a whole scape, which we know has often occurred. J. G. Beer says (quoted by Irmisch, 'Beiträge zu Biologie der Orchideen,' 1853, p. 22) that during three years he tried in vain to fertilise Catasetum, but on one occasion, by placing the viscid disc of a pollinium within the stigma, a ripe fruit was produced; but it may be asked, Did the seeds contain embryos?
