The ferns, although abundant, especially in moist woods from Alaska southward, throughout the continent, reach their greatest variety and richest luxuriance in the West Indies and Central America, where the graceful and most artistically beautiful tree-ferns add an indescribable charm to the always varied foliage. The tree-ferns grow farther up the mountains of the torrid zone than do the larger palms (in the same manner that the smaller ferns extend much farther north than the most hardy palmettoes), and form a conspicuous feature in the foreground of nearly every wide-reaching prospect in the more elevated portions of the West Indies, Central America, and south-central Mexico.
In addition to the palms and ferns, the tropical forests of North America contain a large number of trees of great economic importance. Chief among these are the mahogany, which is native to the lands bordering the Caribbean Sea and Gulf of Mexico, and reaches the largest size and produces the most beautiful and most highly prized wood on Cuba, Haiti, the Bahamas, and Jamaica. As is well known, this hard, dark, heavy, fine-grained, and exceedingly durable wood has been used for the best grades of cabinet-work for about two centuries, and is still unsurpassed for the beauty of its grain, susceptibility of a high polish, and the several ways in which it is adapted for the carver's tool. On account of the great and long-continued demand for its wood it has become scarce in all but the most inaccessible localities. When allowed to reach full maturity it is a large, wide-spreading tree with numerous branches, looking not unlike a giant oak, but has pinnate leaves and small, although somewhat conspicuous, white flowers.
Another gift of the tropical forest is the lignum-vitæ, which furnishes the exceedingly tough, hard, resinous wood preferred above all others for the making of pulleys, mallets, etc. Many other highly prized woods, not known, however, by familiar names, are also found in the varied forests of tropical America, as well as numerous vegetable dyes, such as logwood, brazil-wood, indigo, etc.
The lands of the Caribbean-Gulf region are credited with having introduced to civilized man the potato, Indian corn (maize), and tobacco, although the home of the former is probably in the Andean portion of South America. Indian corn grows luxuriantly not only in the hot lowlands of Mexico, but on the border of the central table-land of that republic, where it is supposed to be indigenous, and has now become one of the leading crops of temperate North America, and is cultivated in many other portions of the world. Tobacco was found under cultivation in Mexico at the time of the first coming of Europeans, and retains for its familiar name the appellation of the district where it was first seen. From Mexico also come the dahlia and the giant sunflower, as well as the various species of aloes and cacti now so common in gardens and conservatories the world over.
Of all the plants, excepting Indian corn and the potato, which are native to the region under review, none has proved such an unalloyed blessing to civilized man as the cacao-tree. As this tree is unfamiliar to most residents of temperate lands, it may not be unprofitable to transcribe in part a description of it from Rhind's Vegetable Kingdom. The tree is very handsome, from 12 to 16 feet high, with an upright trunk some 5 feet high; the leaves are lanceolate, with entire margins, and of a bright-green colour; the flowers are inconspicuous, reddish, with yellowish sepals; the fruit, attached by short stems to both trunk and branches, has a yellowish and reddish colour, oblong, about 3 inches in length, and consists of a fleshy rind, half an inch thick, containing a white pulp in which are imbedded about 25 seeds. The seeds, when roasted, freed from their husks, and ground, furnish the chocolate so extensively
used, especially in France and Spain and in the former Spanish colonies, and is increasing in favour among English-speaking people.
Vanilla, which is used in flavouring chocolate as well as many other dishes, was also found in use among the Aztecs at the time of the Spanish conquest. The vanilla-plant is a climbing vine, with lanceolate leaves 18 inches or more in length, and produces a pod containing bean-like seeds. The pods and seeds when properly dried furnish the flavouring extract of commerce.
Although the trees which yield rubber in America, as well as the cinchona, from the bark of which quinine is obtained, are justly to be accredited to South America, yet certain varieties of these useful plants occur in Central America and are under cultivation as far northward as central Mexico.
A more detailed account of the plants of great utility in one direction or another native to the tropical forests, should include plantains, bananas, and yams, the wide distribution of which, largely by human agency, throughout the torrid zone is well known. The delicious pineapple is native to the Caribbean region, and was found in the markets of the Aztecs by the early Spanish invaders, although perhaps indigenous to other lands as well. In Mexico especially, but on the borders of the tropical forest and in the drier interior, grows the agave, from which the national beverage, pulque, is obtained, and another species of the same peculiarly American family of plants supplies great quantities of the tough fibre known as sisal or henequen hemp, particularly on the stony, arid portions of the peninsula of Yucatan. Of interest to children especially is the fact that Mexico exports some 3,000,000 pounds of chewing-gum each year, which is obtained from a plant there growing wild. To this list of indigenous products may be added ginger, arrowroot, etc., as well as many fruits scarcely known outside the tropics, such as the mango, alligator-pear, breadfruit, and numerous others. This hasty enumeration might be greatly extended or presented in more detail, but probably enough has been said