Epiphytes (ĕp′ ĭ-fīts), commonly called air-plants, since they obtain all their food supplies from the air, having no connection with the soil or with water. They occur in great numbers in the tropics, especially the American tropics, and are found perching in great numbers upon other plants, the trees sometimes being almost covered with them. Many ferns have this habit, but it has been most cultivated by orchids and bromelias. The epiphytic orchids, with their dangling roots and odd-looking but brilliant flowers, are favorite greenhouse-plants. One of the common epiphytes of the United States is the so-called long moss or Spanish moss, which hangs in gray masses among the trees of the gulf states. It is not a moss, but a flowering plant, one of the bromelias.