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AMERICA
flood-plains of all the great rivers of South America, but these are phases of the rivers themselves rather than lakes in the ordinary sense. Lagoa dos Patos and Lagoa Merim on the southern coast of Brazil are shallow brackish lakes shut in by sandbanks thrown up by the sea. There are small lagoons, formed in a similar manner, at many places along the coast in the states of Rio de Janeiro, I*.spirit o Santo, and Alagoas. Lake Maracaibo on the Venezuela coast is a narrow-necked bay rather than a lake. The eastern coast of the South American continent has remarkably few islands, and these are all small, except Trinidad, off the coast of Venezuela, and the Islands. isian(is in the mouth of the river Amazon. The island of Trinidad (area, 1755 square miles) is separated from the continent by the Gulf of Paria. Along the northern end of the island is a range of mountains about 3000 feet high, which are geologically the eastern end of the Cumana range of the Venezuela mainland, with which they were formerly united. On the south side of the island is the famous pitch lake—the most extensive deposit of asphalt known. The island of Fernando de Xoronha, 230 miles off Cape St Roque, is of volcanic origin, and has an area of 12 square miles. Although this island is separated from the mainland by a channel 13,000 feet deep,' it really stands on the deep continental shelf. The Rocas, a small coral island, lies 80 miles west of Fernando de Noronha. The shores of the Falkland Islands (area, 6500 square miles) are indented by long tortuous channels that have the appearance of having been formed by the depression of a hilly land surface. One of these channels quite separates the two main islands. One peak, Mount Adams, has an elevation of 2300 feet. The group is separated from the mainland by a shallow sea, while its flora and fauna show that it was formerly connected with the Patagonian mainland. The Tierra del Fuego group of islands and the other islands that border the south-west coast, from the Strait of Magellan to latitude 42°, by their flora, fauna, the land forms and the forms and depths of the channels about them, show that they were not long ago, geologically speaking, a part of the mainland, from which they have become separated by the depression of the southern portion of the continent. This depression has admitted the sea to the lower valleys, making fjords of them, while the highlands and mountain tops remain projecting from the water as islands.1 The flora of South America embraces a large number of peculiar types originating either in the highlands of Brazil or in the Andes region. Several of our most useful plants are natives of the South American tropics. Among these are the rubber-producing plants, cotton, potatoes, maize, the cinchona, Paraguayan tea, ipecac, vegetable ivory, coca, and the chocolate plant. Other tropical and subtropical plants, such as coffee, sugar-cane, oranges, and bananas have been introduced, and are extensively cultivated. The flora of the Amazon valley may be taken as the type of that of the moist valleys. The forests are almost impenetrable; roads through them are soon closed by the rank growth, and vines, creepers, and climbing plants turn them into veritable mats down to the water’s edge. Bamboos reach an enormous size and form extensive thickets along certain streams. Palms are the most characteristic and beautiful trees, and reach their greatest development in the Amazon 1 The continent of South America has nearly all been explored after a fashion, but much of it has never been mapped. The statements frequently met with to the effect that there are large unexplored tracts should be taken with allowances. The various governments have concerned themselves but little with explorations and mapping, and whatever has been accomplished has been done incidentally rather than for the direct purpose of determining the geography and topography.
[south
valley. They take on a great variety of forms : some have a height of 100 feet or more, others are no larger than a lead pencil and only a yard high; some are trunkless, while others are slender and climb like vines. A noteworthy feature of these tropical plants is .that they seldom form forests of a single or of a few species, as so often occurs in the temperate zones. The shaded woods of the forests in many places abound in beautiful ferns, some of them reaching the dimensions of trees. The plants of the campos and plains have a stunted appearance. The grasses are wiry and tough, in places spreading evenly over thousands of square miles of nearly level marshy lands, as in the Gran Chaco of the Paraguay valley, in others growing in tufts over the sandy plains. In the high table-lands of Southern Brazil, the araucarian pine grows in beautiful forests as far north as Barbacena, state of Minas. In the north-west, the western slopes of the mountains are covered with a dense tropical vegetation high up their sides, while on the east they are comparatively bare. In the high mountains, the flora, though scant, resembles that of temperate regions. Sixty per cent, of the genera are like those of the temperate zones, but the species are peculiar to the Andes. On the lofty peaks Whymper collected, of flowering plants, fifty-nine species above 14,000 feet; thirty-five species above 15,000 feet; and twenty species above 16,000 feet. The fauna of South America includes a large number of species, but relatively a small number of individuals. With local exceptions, this seems to be true of pauna all the forms of life. The land mammals are nearly all small. There are many species of monkeys, all of them arboreal. The only reptiles that are at all abundant are lizards, and, in some places, alligators. There are only two large snakes, the boa constrictor and the water boa, and they are not abundant. The other kinds of snakes are represented by a small number of individuals. Certain ruminants having long woolly hair, the llamas, alpacas, and vicunas, are found only in the high Andes. The llama has been domesticated, and is used for carrying small burdens. The condor, the largest living bird of flight, inhabits the lofty Andes. The insects of the highest peaks are related generically, but not specifically, to those of the temperate latitudes of North America, a fact interpreted by biologists to mean that, probably on account of some obstacles to free movement since the Glacial epoch, there has been no migration along the Andes during the existence of living species. (j. c. Br.) South American Meteorology. South America lies between the mean annual isotherms of 40° and 80° Fahr. The northern and north-eastern portions of the continent, down nearly to the C11 mate. tropic, are within the district enclosed by the mean annual isotherm of 80°. The cold Peruvian current deflects the isotherms strongly equatorwards along the Pacific coast, especially between latitudes 30° S. and the equator, while these same isotherms loop strongly polewards over the land. The equatorward deflexion on the west coast results in giving places on that coast much lower temperatures than those of stations in corresponding, or even considerably higher, latitudes on the east coast. Lima, in latitude 12° S., has a mean annual temperature of 66•2°; Rio de Janeiro, which is nearly on the tropic on the east coast, has a mean annual of 72T°. The mean annual temperatures on the Atlantic coast between latitudes 30° and 40° S. are about 5° higher than those in corresponding latitudes on the Pacific coast. The average position of the heat equator (axis of the equatorial belt of high temperature) is on the immediate sea-coast in North-
