thumb nail. Tnere are places wnere not only every available Inch of soil is carpeted with them, but they cover the trees, roc and branch, 'dinar to the rough tree trunk* and even to the tree ferns themeslves. Another variety forms a vine that clambers un the trees or anything else it can find to cling to, to a height of twenty feet or more.Probably the most beautiful variety are known as the filmy ferns. Nature has deprived them of the outer layer of tissue, and they are almost transparent, so that the delicate veinlng and the still more delicate tracery of the cell wails in plainly visible. This beautiful species is Largely if not completely represented in the collections secured by Dr. Underwood.The luxuriance of tropical vegetation in Jamaica was, illustrated by ferns which had overgrown an abandoned plantationwhich Dr. Underwood visited. Every path was made impassable by the plants until the two negro guides had matted them down for the others of the party. One threw himself on the mass and rolled it down by the weight of his body. His companion followed treading and stamping the plants still more compactly. The explorer! found themselves at times upheld fourfeet above the ground by the matted plants.