Page:Darwin - The various contrivances by which orchids are fertilized by insects (1877).djvu/239

. VII. Although Mormodes ignea is an hermaphrodite, yet it must be as truly diœcious in function as Catasetum; for as it takes from twelve to fifteen minutes before the pedicel of an ejected pollinium straightens itself and the anther-case drops off, it is almost certain that within this time an insect with a pollinium attached to its head would have left one plant and flown to another.

Mormodes luxata.—This rare and fine species is fertilised in the same manner as Mormodes ignea, but differs in several important points of structure. The right and left sides of the same flower differ from one another even in a greater degree than in the last species. One of the petals and one of the sepals project at right angles to the column, while the corresponding ones stand upright and surround it. The upturned and twisted labellum is furnished with two large lateral lobes: of these one embraces the column, while the other stands partly open on the side where the one petal and sepal lie flat. Insects can thus easily enter the flower on this latter side. All the flowers on the left side of the spike are open on their left sides, while those on the right side are open on this side. The twisted column with all the important accessory parts, together with the rectangularly bent apex, closely resemble the corresponding parts in M. ignea. But the under side of the labellum does not rest on and press against the rectangularly bent apex of the column. This stands free in the middle of a cup formed by the extremity of the labellum.

I did not obtain many flowers fit for examination, as three had ejected their pollinia owing to the shocks received during their journey. I pricked deeply the labellum, column and stigma of some of the flowers without any effect; but when I lightly touched with a