EPIPHYTES are plants grossing upon other vegetables, adhering to their bark, and rooting among the scanty soil that occupies their surface, in which respect they aro distinguished from parasitical plauta, which, like mistletoe and the various species of Lora- nthus, strike their abortive roots into the wood, and flouriali upon the juices of the individual to which they attach theuiselves. Orchidaceous epiphytes grow upon treeis the recesses of tropical forests; and Dr. Wallich found them growing equally well in Nepal upon trees and stones, provided the latter hail a certain quantity of mould and moss adhering to them. In the Malay Archipelago, the mean temperature of which is estimated at between 77° and 78°, and is very damp; they are found in profusion ; while on the continent of India they are almost unknown, their place being occupied by parasitical Loranthi. At the estuaries, howevert of the Ganges, tho Brahmaputra, the Irawadi, and the rivers of Ifartaban, they exist in vast quantities, but all these stations arc excessively damp. In the Botanic Garden at Calcutta they grosv most vigor ously during the rainy season but in the fiercely hot season, which begins in Itlarch, aud lasts till the 10th of June, they perish, notwithstanding the care they receive.
In Nepal, orchidaceous epiphytes grow in company with ferns, and the thicker the forest, the more stately the trees, the richer and blacker tho natural soil, the more profuse the orchidacem and ferns upon thein. There they flourish by the sides of dripping springs, in deep shady recesses, in inconceivable quantity, and with an astonishing degree of luxuriance.
Reiuwardt speaks of great quantities of orchi daccze in the storax and laurel woods of Java, growing along with nepenthes, rhododendrons, magnolim, and oaks, in a zone of vegetation whose lower limit is 3000 feet above the sea. Dendrobium nobile, Renanthera coccinea, and some others, bear the periodical cold of Canton, where it occasionally freezes. Dendrobium eaten atum and D. rnoniliforme occur in Japan its far north as 37° or 38°, or the parallel of Lisbon, and are periodically subject to a very low temperature ; and Dr. Royle inet with the deciduous Caelogynes and Dendrobium alpestre on the Himalaya moun tains, at the height of 7500 feet, where suow sonietimes lies in winter for a week or more.