The floral area of North America, defined by form and climate, may be divided into five belts : the eastern forested area, the west ern forested area, the interior unforested area, the northern barren lands and the torrid coasts. The eastern forested area extends from the Laurentian highland in Canada southward to the Gulf and Atlantic coast east of the Mississippi; in the north and south ward along the mountains the trees are largely conifers with a mixture of birches, poplars and maples; southward, especially in the interior and at low levels, the conifers almost disappear and oaks, hickories, plane-trees, tulip-trees, walnuts and other valu able deciduous trees are in abundance; the long-leaf pine charac terizes the low coastal margin. The western forested area begins in the Rocky mountains and extends to the Pacific, but does not de scend below the lower timber line into the dry intermont basins of middle latitudes ; northward in Canada, the forest is continuous from the upper timber line down into the valleys ; it attains a lux urious and dense development along the rainy coast, where the redwood (Sequoia) of northern California and Oregon reaches a height of from 30o to 400 feet. The unforested area of the interior includes two dissimilar regions. On the east are the fertile prairies, spreading between the middle Ohio and the upper Great Lakes and extending beyond the Mississippi ; here the native grasses and herbaceous vegetation are now largely replaced by agricultural crops. On the west under a drier climate vegetation is more scanty; but far north a wooded belt connects the eastern and western forests across the medial plains. Aridity and barrenness increase south-westward into California and southward into Mex ico; on this broad desert few trees are found, although pilions grow on cliffs and ledges and cottonwoods are found along water courses; and the mountains that rise above the desert carry for ests. The desert vegetation consists of cactus, agaves, sage-brush (Artemisia) and other dry-climate plants in large variety. In the far north are the "barren lands," with their permanently frozen. subsoil ; the growing season here is short and trees cannot de velop, although birches, poplars, willows and some other kinds that attain good size southward are here present as dwarfed shrubs. The torrid coasts support a tropical vegetation ; it is somewhat developed in Florida and becomes dominant in Mexico and Central America. (W. M. D.; P. H. 0.) In the accompanying table are given the best available data regarding the numbers of people in the major political divisions of North America and the islands in the Caribbean sea generally classed as belonging to this continent. Unfortunately, there are no actual census counts available for some of the smaller coun tries. The data in column B tell whether the figures given in column C are census figures or estimates and the date on which they were presumably gathered.
The most complete and accurate statistics are those for the United States and Canada, whose censuses of 193o and 1931 re spectively have been published. Comparatively reliable figures are also offered by the governments of such British possessions as Jamaica and the Bahamas and the French Islands of Guadeloupe, Martinique, and St. Pierre and Miquelon. Four of the Central American Republics have recent censuses. But the Mexican cen sus of 193o has not yet been fully compiled and the total for that country is therefore merely a preliminary estimate.
In column D is given the density per square mile of the pop ulation in the different countries. It will be seen from these data that some of the smaller islands among the West Indies are very densely populated, indeed they are among the most densely peo pled parts of the world. Jamaica, Porto Rico and Haiti are also
quite thickly settled, their density being comparable to that of France.
In column E are given the populations of the same areas in 1881 or thereabouts-4o years earlier. It will be seen that the population of the continent has almost doubled during this time.
In the West Indies there are great differences between islands, but the predominant stock in the tropic isles is negro, very gen erally mixed with white stock and in some cases with Indian stock. The amount of pure white stock is nowhere very large. This statement holds in spite of the fact that Porto Rico reports about 72% of its inhabitants as white.
In the United States certain racial lines are closely drawn. Of the total population in 1930 there were 11,891,143 or 9.7% classed as Negro, 1,422,533 or 1.2% as Mexicans and about 0.5% as of other races. The white stock constituted 88.7%. In Canada the number of Negroes was only 19,456 in 1931, Indians only 122,91r and Asiatics 84,548. The important distinction in Canada, however, is that between British and French, the former consti tuting 51.8% of the total population in 1931, while the latter con stituted 28.2%. Thus Canada, unlike most other countries in North America, has no real "colour problem" but only a "lan guage problem." The total population in North America in 193o was approxi mately 167,000,00o, or about one-third that of Europe. This population was scattered over an area 2.25 times as great so that its density was only about one-sixth that of Europe. (W. S. T.) The Indians of North, as of South, America are believed to have had their origin in the eastern hemisphere. In the New World there are no unquestioned fossils of human ancestors or extinct human races, such as Europe, Africa, Asia and Oceania contain. Then, many regions of the Old World are studded with sites con taining implements and refuse of pure Palaeolithic type, whose geological formation and associated animal bones leave no doubt that they were occupied during the Pleistocene or glacial era; but in America there are no such sites, implements of Palaeolithic type being normally found in association with Neolithic ones.