Page:Popular Science Monthly Volume 26.djvu/703

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A NATURALIST'S EXCURSION IN DOMINICA.
685

ers and the luster of their leaves. In some epiphytal orchids, aroids, and ferns, the roots weave themselves on their bark support into something like birds' nests, in which are gradually accumulated dead leaves and other organic detritus, to form a humus. The fourth class, to which the bromelias belong, is distinguished from all the others by the fact that water and food are taken up by the leaves, while the roots are either not developed, or are reduced to mere organs of attachment. The Tillandsia usneoides ("Spanish moss"), which, having no roots, hangs from the limbs, is clothed with a silver-gray hair, having shield-like processes which represent water-absorbing organs. Other epiphytic bromelias have similar absorptive vessels, and special provisions in the dish-like arrangement of the leaf-rosettes for storing rain-water and dew and more solid food for a considerable time. One may be convinced in a very instructive manner of the presence of water in these leaf-basins, by bending down a limb covered with epiphytes, when, unless he proceeds very carefully, he will receive a quart or more of water on his head. We learn from these considerations that these epiphytes are not real parasites, but only tenant forms, which, fixing their homes on other plants, derive their food support from the atmosphere and from dead matter. There are, however, besides these, real parasites at Laudat, which prey upon the living wood of the trees.

Among the forms of animal life at Laudat are three hummingbirds, one of which is so tame that the children catch it in their hands, and another is hardly two inches long; and, in sharp contrast with them, the largest of all insects. This is a beetle, which entomologists have named, in recognition of its gigantic size and great strength, Dynastes Hercules. The male is armed, like our stag-beetles, with two immense tusk-like processes on the head, the physiological significance of which is unknown. The female is unarmed, and of much more slender constitution.

So absorbed were we in the contemplation of the new forms of life around us that we would have been unmindful that the afternoon was passing away were it not that a bird called out to inform us that the sun would set in half an hour, and ten minutes later it would be dark. The sunset-bird, as the American Ober, who discovered it in this island, has named it in his "Camps in the Caribees," utters its peculiar cry only twice during the day—half an hour before sunrise, and as long before sunset—and keeps complete silence for the rest of the day. For a very brief interval after sunset the air is perfectly clear and transparent, and the light-effects are most picturesque; then, as if some signal had been given, begins the concert of the tree-frogs and locusts, and finally darkness settles over the landscape, to be broken up shortly by the rising of the moon, whose light gives a new series of picturesque effects.

Early in the morning we are awakened for a bath at the junction