The tree is one of the most majestic in the South American forests, attaining a height of 100 or 150 feet. Its trunk is straight and cylindrical, and measures about 3 or 4 feet in diameter. The bark is grayish and very even. At a distance, the tree somewhat resembles a chestnut. Its branches are alternate, open, very long, and droop toward the earth. The leaves are alternate, oblong, short petioled, nearly coriaceous, about 2 feet long by 6 inches wide, entire or undivided, and of a bright green color. The flowers have a two-parted, deciduous calyx, six unequal cream-colored petals, and numerous stamens united into a broad, hood-shaped mass, those at the base being fertile, and the upper ones sterile. The fruit is nearly orbicular, and about 6 inches in diameter, and has a hard shell about half an inch thick, which contains from 18 to 24 triangular, wrinkled seeds that are so beautifully packed within the shell that when once disturbed it is impossible to replace them. When these fruits are ripe, they fall from the tree and are collected into heaps by troops of Indians called _Castanhieros_, who visit the forests at the proper season of the year expressly for this purpose. They are then split open with an ax, and the seeds (the Brazil nuts of commerce) taken out and packed in baskets for transportation to Para in the native canoes. The "meat" that the Brazil nut contains consists of a white substance of the same nature as that of the common almond, and which is good to eat when fresh, but which, by reason of its very oily nature, soon gets rancid. Besides its use as an article of dessert, a bland oil, used by watchmakers and artists, is obtained from the nut by pressure. Brazil nuts form a considerable article of export from the port of Para, whence they are sometimes called Para nuts. The Brazil nut tree remained for a long time unknown to European botanists, although the fruit has been from a very remote epoch consumed in large quantities in certain southern countries of the New World. The first description of the tree we owe to Humboldt and Bonpland, who established the genus and species in the botanical part of the account of their voyage. The genus is dedicated to the illustrious Berthollet. "We were very fortunate," say these authors, "to find some of these nuts in our travels on the Orinoco. For three months we had been living on nothing but poor chocolate and rice cooked in water, always without butter, and often without salt, when we procured a large quantity of the fresh fruits of the _Bertholletia_. It was along in June, and the natives had just gathered them."