Another beard-like lichen (Usnea florida), often growing along with the rock-hair, is gathered in great quantities in North America, from the pine-forests, and stored up as winter fodder for cattle in inclement seasons. Goats, and especially deer, are fond of it; and in winter when other food is scarce, they hardly leave a vestige of it on the trees within their reach. The tortoises of the small rocky islands of the Galapagos Archipelago subsist almost entirely upon it. In Scotland it is one of the most picturesque ornaments of the pine-forests. When fully developed it forms tufts nearly a foot in length. It is quite a miniature larch-tree, with root, stem, and most intricate branches and twigs. Its color is pale sea-green; and a central white thread or pith runs through the main stem, and lateral branches, on which, when cracked with age, the segments of cellular tissue are strung like beads on a necklace. A kind of farinaceous meal is plentifully sprinkled on the ultimate branches. Altogether it is one of the most beautiful and interesting lichens. A reddish variety grows in such quantities on trees of Conyza arborea, forming the alley near Napoleon Bonaparte’s residence in St. Helena, that this hanging vegetation is the first thing that attracts the eye of the visitor. But it is not to animals alone that lichens furnish a supply of food. There are few, I presume, who are not acquainted with some particulars regarding the history and uses of that remarkable lichen sold in chemists’ shops under the name of Cetraria islandica, or Iceland moss. What barley, rye, and oats are to the Indo-Caucasian races of Asia and western Europe; the olive, the grape, and the fig to the inhabitants of the Mediterranean districts; the date-palm to the Egyptian and Arabian; rice to the Hindu; and the tea-plant to the Chinese--the Iceland moss is to the Laplanders, Icelanders, and Esquimaux. It may be mentioned that, notwithstanding its name, the Iceland moss is not only more plentiful, but more largely developed in all its varied forms in Norway than in Iceland, and it is in Norway that it is now almost exclusively collected for the European market. Those who have read the affecting account which Franklin and Richardson give of their expedition to Arctic America must be familiar with the name of the Tripe de Roche, which occurs on almost every page, and is intimately associated with the fearful sufferings which these brave men endured, a part of which only would have sufficed to unseat the reason of most individuals. During their long and terrible journey from the Coppermine River to Fort Enterprise, one of the stations of the Hudson’s Bay Company, in the almost total absence of every other kind of salutary food, their lives were supported by a bitter and nauseous lichen, to which the name of Tripe de Roche (Gyrophora) has been given as if in mockery.