Page:Popular Science Monthly Volume 36.djvu/374

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THE POPULAR SCIENCE MONTHLY.

charm that captivates. Their colors are harmoniously toned, and always bright and elegant. Their odor is sweet and penetrating, but does not cloy. Notwithstanding their thin texture, which gives them a delicate and frail air, they last longer than other ornamental flowers. Nothing, in fact, seems to be wanting to them but a more lively and abundant foliage; and that can be supplied by mingling fern-leaves with them.

It was long supposed that these wonderful plants were extremely delicate and capricious. This was a mistake. To their other virtues they join the rare one of simplicity.

Nearly all the orchids cultivated in greenhouses are natives of the intertropical zone, and it was supposed from this fact that they required considerable heat. But it has gradually been established that a high temperature really hinders their best development. A considerable number of them in their native state grow on high mountains, under exposure to a bracing atmosphere; and they are now cultivated in moderately warmed and freely ventilated greenhouses. They are therefore relatively hardy plants, well adapted to the decoration of our rooms.

The genera and species of orchids already known are very numerous, but the varieties are more so. The cause of the multiplicity of form, shade, and appearance lies chiefly in the organization of the flower. Without going into technical details and descriptions, it is enough to say that the pollen is not spontaneously carried to the stigma, and that a foreign agent has to intervene in the fertilization of the seed. The office is discharged by insects, which visit the flowers for their honey and involuntarily load themselves with pollen; then, flying from one flower to another of different varieties and species, they effect all kinds of mixtures. Consequently, varieties are endlessly multiplied. While many of these may be common, others obtain special hues or streaks, which render them rare and cause them to be sought out by collectors. Now that orchids are in full favor, and are likely to continue so for a long time, enormous prices are paid for the choice varieties.

A Cattleya (Fig. 1), shown at a recent horticultural exhibition in Paris, had a light violet-blue corolla instead of the usual rose-violet. This sport in color was enough to raise the price of the plant to ten thousand or twelve thousand francs. The owner—M. Piret, of Argenteuil—had himself sought out the variety in the forests of Venezuela. The instance is not a rare one. At a recent sale in Ghent, every specimen of a certain Cypripedium brought six thousand francs; and like prices are often obtained in England. The ordinary prices in trade are, however, more moderate than this. As the result of numerous explorations, often made at great risk of life, orchids of all kinds and of the more usual varieties have been imported by thousands within the last