Of all the forest giants of Guayana, Schomburgk considered the mora the most magnificent; the average diameter of the trunk is about three feet, and it seldom branches at less than forty feet from the ground. The dark-red, fine-grained wood is said to be excellent for shipbuilding purposes. Mahogany or _caoba_, the _palo de arco_, whose wood is very like mahogany in colour, and a big tree called in Venezuela rosewood, which it resembles, are among the timber trees of the region known to us in Europe. The huge _ceibas_, with their buttress-like roots, have a soft, easily worked wood, excellent for the dug-out canoes of the Indians, and the equally large _mucurutu_ or cannon-ball tree furnishes a beautiful but hard and fine-grained timber. Unfortunately, the very fertility of the soil becomes a drawback in the exploitation of these timber resources, for all trees grow with equal freedom, and the particular kind for which the lumber-man is searching may only be found at rare intervals; on a large scale, when all the valuable woods are utilised, this difficulty would, to some extent, disappear. There are two fruit-trees whose products are well known in European markets, and though these grow all over Guayana, they are particularly abundant in certain regions. The Brazil nut was first described by Humboldt, but since his time it has become a common article of merchandise in Europe; the tree which bears it is itself large, and the fruit, with its fifteen or twenty nuts, is tremendously heavy, and generally breaks in falling from the tree when ripe, not infrequently cracking the shells inside, when the birds and monkeys are able to enjoy the oily kernel; otherwise the exterior usually proves too hard. The other fruit we have referred to is the _sarrapia_, or tonka-bean, not so well known to the general public of to-day as formerly, though extensively used in perfumery. The trees grow in greatest abundance and excellence, according to André, in the Caura and Cuchivero valleys. The gums and resins of Guayana include the balatá, copaiba-balsam, and rubber-producing trees, the latter chiefly varieties of Hevea, while _cinchona_ or quinine with innumerable creepers and trees possessed of medicinal or toxic properties are found everywhere. The 2,450 species of plants referred to by Schomburgk have since been added to, and it is obvious that in such an assembly there must be many of value, as yet undiscovered and unused. The vegetation of the higher exposed peaks and plateaux is quite different from that of the forests, and here Schomburgk found such an alpine, or rather Arctic, form as reindeer-moss, associated with semi-tropical rock-orchids and aloes. The forest plants and trees of Guayana also flourish in the Delta region and in the forests bordering the Llanos of Maturín, but the vegetation of northern Venezuela is generally very different from that of the south.