Page:Darwin - The various contrivances by which orchids are fertilized by insects (1877).djvu/223

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Chap. VII.
MYANTHUS BARBATUS.
203

every naturalist, but can never be observed without renewed interest. At a period not far distant, naturalists will hear with surprise, perhaps with derision, that grave and learned men formerly maintained that such useless organs were not remnants retained by inheritance, but were specially created and arranged in their proper places like dishes on a table (this is the simile of a distinguished botanist) by an Omnipotent hand "to complete the scheme of nature."

The third form, Myanthus barbatus (fig. 31, B), is sometimes borne on the same plant together with the two preceding forms. The flowers differ greatly in external appearance, but not in essential structure, from those of both the other forms. They generally stand in a reversed position, compared with those of Catasetum tridentatum and of Monachanthus viridis, that is, with the labellum downwards. The labellum is fringed in an extraordinary manner with long papillæ; it has a quite insignificant medial cavity, at the hinder margin of which a curious curved and flattened horn projects, which represents the anvil-like projection on the labellum of the male C. callosum. The other petals and sepals are spotted and elongated, with the two lower sepals alone reflexed. The antennæ are not so long as in the male C. tridentatum; they project symmetrically on each side of the horn-like process at the base of the labellum, with their tips, which are not roughened with papillæ, almost entering the medial cavity. The stigmatic chamber is of nearly intermediate size between that of the male and female forms; it is lined with utriculi charged with brown matter. The straight and well-furrowed ovarium is nearly twice as long as that of the female Monachanthus, but not so thick where it joins the flower; the ovules are opaque and pulpy after having been kept