XI. Bamboos (Gramituro).—The bamboos and their allies are the grass trees of the trop ics. They furnish cheap wood for the poorer classes for construction purposes and for al most every use to which wood can be put. Bamboos are more abundant in the eastern than in the western tropics where, besides occurring as constituent parts of some wild forests, they are extensively planted, also to some extent throughout the western tropics. The construc tion bamboos belong principally to certain spe cies of the genera Bambusa, Arundinaria and Dendrocalamus. While wild bamboos occur in the western tropics and are cultivated to some extent, they do not play so important a part in the life of the people. In certain parts allies of the bamboos or canes take their place. These are the cana brava (Gyneeium sagitta tum [Aub1.1 Beauv.), and species of Guada known locally in the Amazon as taboca and in Ecuador under the market name of Guayaquil cane. This is rather extensively exported as a construction wood to the dry treeless coastal regions of Peru and Northern Chile.
XII. Palms (Palma).— In regions where bamboos are not abundant palms largely take their place as construction timbers. Besides they furnish a large number of minor forest products. Certain palms produce food, in others the nutsproduce valuable oils, and some yield wax, from others vegetable ivory is ob tained. Besides the cocoanut and the date palms which are really not forest products, the following are mentioned because they produce products that arc extensively exported: 1. The ivory nut palm or vegetable ivory. —The ivory nut is the product of a numbcr.of species of the genus Phytelephas. It is found in portions of Ecuador, Colombia and the Ama zon. At present it is one of the principal ex ports of Ecuador and this country is the chief source of the nuts. Ivory nuts are principally used for buttons, but many small objects like checkers, chess, etc., are made from it.
2. Rattans.—The rattans of commerce are the product of several species of the genus Cala mus and related genera. They are climbing palms, in some cases they reach the great length of 400 or more feet, and clamber from tree to tree in the forests. They are confined to the eastern tropics. They furnish the main cordage of the countries in which they grow. When exported and in the round they arc used for canes, umbrella handles and for making chairs; and *split* rattans find their greatest use for seats and backs of chairs.
3. The Oil Palm.—The nut of this palm is extensively exported from West Africa for the valuable oil it contains. It is also found in Brazil where it was introduced from Africa.
Here it is used locally only. It is the product of Elceris 4. Was 'Palm.— This palm•yields a wax that comes from scales on the underside of the leaf. The palm is Copernicia cerifera L. and is ex ported mainly from northeastern- Brazil.
5. The'Panama Hat Palm.— This belongs to the Cyclanthacece, a. family closely related to the palms. The species that furnishes the for Panama hats is Corludovica pal mata. R. and P. The making of Panama hats is a very important industry in Ecuador, and 'neighboring parts of Peru and Colombia.
XIII. Rubber, Guttapercha, The Xiii. Rubber, Guttapercha, The trees and other plants that produce the rubber of commerce are found in many parts of the tropical world. The principal one of these is
Hevea braziliensis Muell. Arg. (Euphorbiacee), a tall tree, native of the vast Amazon region. Formerly most of the rubber of commerce was collected from this region. While the supply from the Amazon valley has not decreased, the increasing demand for rubber has been 'met by the extensive rubber plantation of the Malay Peninsula and neighboring regions, principally Ceylon, Sumatra, Burma and Borneo. The eastern tropics now produces fully 80 per cent of the world's supply of crude rubber. The commercial name of rubber from Hevea brazili ensis and certain other species is Pard rubber. It has the local name of seringa. Ceara rubber (Manihot Mfill. Arg. and other spe cies) locally known as Manitoba, belongs to the same family as the Para rubber. It comes from the dry regions of northeastern Brazil and is cultivated to some extent in other parts of the tropics. Next to Para rubber in importance is the so-called Castilloa rubber, the product of Castilla elastica Cerv. and other species of this genus and belongs to the family Moracea'. It is a native of tropical America from southern Mexico to the Amazon region. In Brazil it is known as caucho in distinction from the seringa (Para rubber). This rubber tree has been cul tivated extensively.
The Mangabeira rubber, mainly the product of Hancornia speciosa Gom. belongs to the family Apocynacece. It is found throughout the region from the territory of Acre, Brazil, to southern Parana, Brazil, and in adjoining regions of other countries. It is cultivated to some extent hut as yet the cultivated rubber is not commercially important. To this family also belong the African wild rubbers, princi pally species of the genera Landolphia and Kick.ria.
Gutta percha is not a rubber, for it is plas tic rather than elastic. It comes from trees that belong to the family Sapotacecr, mostly certain species of the genera Payena and Palaquium that are found only in the Indo-Malay region. In the western tropics balata, mostly the prod uct of Mimusops balata Gartner., is the near est to gotta percha. It comes mainly from the Guianas and Venezuela.
Chicle is the source of the chewing gum of commerce. It is the gum of a tree known under common names of sapodilla or nispero and other local names. This is Achras zapota L. The chicle of commerce comes mostly from southern Mexico where the tree is native. It is planted, however, in other tropical countries.
Botilger, G. S., 'Wood: a Manual of the Natural Histories and Industrial Applications of the Timbers of Commerce' (2d ed., London Gamble, J. S. 'A Manual of Indian Timbers) (London 1902) ; Foxwor thy, F. W., 'Indo-Malayan Woods' (Tht Phil ippine Journal of Science, C. Botany, pages 409-592, Vol. IV, Manila 1909) ; Whitford, H. N., 'The Forests of the Philippines' (Bull. No. 10, Bureau of Forestry, Manila, P. I., 1911); Navarro de Andrade, Edmund() and Vecchi, Octavio, 'Les Bois Indigines de Sao Paulo' (Sao Paulo, Brazil 1916) ; Pereira, H., 'The Timber Trees of the State of Sao Paulo Brazil' (Sao Paulo, Brazil) ; Huber, H., 'Mattas e Madeiras Amazonicas' (pages 91 216, Vol. VI, Boletim do Museu Goeldi 1910, Path, Brazil).
H. N. Warreosm, Yale School of Forestry.