Page:EB1911 - Volume 04.djvu/461

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FAUNA]
BRAZIL
 443


Fortaleza) of nearly 80° F., which is slightly higher than those of Maranhão and Pará. At Pernambuco the mean summer temperature is 79.5° and that of winter 76.8°, which are about 3° lower than the mean temperature of Bahia in summer, and 5° higher than the Bahia mean in winter. South of Bahia there is a gradual increase in the rainfall, that of Rio de Janeiro exceeding 43 in. per annum. At Santos the rainfall is exceptionally heavy and the mean temperature high, but below that point the climatic conditions are considerably modified, the range in temperature being greater, the mean annual temperature lower, and the rainfall more evenly distributed throughout the year. The winds are more variable, and the seasons are more sharply defined. In Rio Grande do Sul the range in temperature is from 26° to 80°, the climate being similar to that of Uruguay. At Pelotas, a sea-level port on Lagôa dos Patos, the mean annual temperature is about 63° and the annual rainfall about 42 in. Extreme variations in temperature are often produced by cold south-west storms from the Argentine pampas, which sweep across southern Brazil as far north as Cape Frio, the fall in temperature sometimes being 22° to 27°. These storms usually last from two to three days and cause much discomfort. Winter rains are more frequent in southern Brazil, and violent storms prevail in August and September. At Blumenau, on the Santa Catharina coast, the annual rainfall is 53 in.

The climatic conditions of the Brazilian plateau are widely different from those of the coast in many respects. There is less uniformity in temperature, and the elevated chapadas are generally hotter during the day and cooler at night than are localities of the same latitude on the coast. The Brazilian Guiana plateau, lying immediately north of the equator, is in great part a hot, stony desert. Geographically it belongs to the Amazon basin, as its western and southern slopes are drained by tributaries of that great river. Climatically, however, it is a region apart. It lies in the north-east trade winds belt, but the mountain chain on its northern frontier robs these winds of their moisture and leaves the greater part of the Brazilian plateau rainless. Its eastern and western extremities, however, receive more rain, the former being well forested, while the latter is covered with grassy campos. South of the Amazon valley and filling a great part of the eastern projection of the continent, is another arid, semi-barren plateau, lying within the south-east trade winds belt, and extending from Piauhy southward to southern Bahia. It covers the state of Piauhy and the western or inland parts of the states of Ceará, Rio Grande do Norte, Parahyba, Pernambuco and Bahia. The year is divided into a dry and wet season, the first from June to December, when rain rarely falls, the streams dry up and the campos are burned bare, and the second from January to May when the rains are sometimes heavy and the campos are covered with luxuriant verdure. The rains are neither regular nor certain, however, and sometimes fail for a succession of years, causing destructive sêccas (droughts). The interior districts of Ceará, Pernambuco and Bahia have suffered severely from these sêccas. The sun temperature is high on these barren tablelands, but the nights are cool and refreshing. The prevailing winds are the south-east trades, which have lost some of their moisture in rising from the coastal plain. In summer, becoming warmed by the heated surface of the plateau, they sweep across it without a cloud or drop of rain. In winter the plateau is less heated, and cold currents of air from the west and south-west cause precipitation over a part if not all of this region. South and south-west of this arid plateau lie the inhabited tablelands of Rio de Janeiro, São Paulo and Minas Geraes, where the climate is greatly modified by a luxuriant vegetation and southerly winds, as well as by the elevation. Minas Geraes is forested along its water courses and along its southern border only; its sun temperature, therefore, is high and the rainfall in its northern districts is comparatively light. São Paulo is partly covered by open campos, and these also serve to augment the maximum temperature. In both of these states, however, the nights are cool, and the mean annual temperature ranges from 68° to 77°, the northern districts of Minas Geraes being much warmer than the southern. In São Paulo and southern Minas Geraes there are sometimes frosts. In the Parahyba valley, which extends across the state of Rio de Janeiro, the mean temperature is somewhat higher than it is in São Paulo and Minas Geraes, and the nights are warmer, but the higher valleys of the Serra do Mar enjoy a delightfully temperate climate. The rainfall throughout this region is abundant, except in northern Minas Geraes, where the climatic conditions are influenced to some extent by the arid eastern plateau. South of São Paulo the tablelands of Paraná, Santa Catharina and Rio Grande do Sul enjoy a temperate climate, with an abundant rainfall. There are occasional frosts, but snow is never seen. Of Goyaz and Matto Grosso very little can be said. The lower river valleys of the Tocantins-Araguaya, Xingú, Tapajós and Paraguay are essentially tropical, their climate being hot and humid like that of the Amazon. The higher valleys of the Paraná and its tributaries, and of the rivers which flow northward, are sub-tropical in character, having high sun temperatures and cool nights. Above these, the chapadas lie open to the sun and wind and have a cool, bracing atmosphere even where high sun temperatures prevail. The mean annual temperature at Goyaz (city), according to a limited number of observations, is about 77°. There is no absolutely dry season in this part of the great Brazilian plateau, though the year is customarily divided into a dry and wet season, the latter running from September to April in Goyaz, and from November to April in Matto Grosso. The prevailing winds are from the north-west in this region, and westerly winds in the rainy season are usually accompanied by rain.

Fauna.—The indigenous fauna of Brazil is noteworthy not only for the variety and number of its genera and species, but also for its deficiency in the larger mammals. Of this, one of the best authorities on the subject (H. W. Bates in The Naturalist on the River Amazons) says: “Brazil, moreover, is throughout poor in terrestrial mammals, and the species are of small size.” It is noteworthy, also, for the large number of species having arboreal habits, the density and extent of the Amazon forests favouring their development rather than the development of those of terrestrial habits. Of Quadrumana there are about fifty species in Brazil, all arboreal, thirty-eight of which inhabit the Amazon region. They belong mostly to the Cebidae family, and are provided with prehensile tails. The Carnivora are represented by six species of the Felidae, the best known of which is the onça, or jaguar (F. onça, L.), and the cougar, or puma (F. concolor); three species of the Canidae, the South American wolf (C. jubatus), and two small jackals (C. brasiliensis and C. vetulus); and a few species of the Mustelina including two of the otter, two Galictis and one Mephitis. Of the plantigrades, Brazil has no bears, but has the related species of raccoon (Nasua socialis and N. solitaria), popularly called coatis. The opossum (Didelphis) is represented by three or four species, two of which are so small that they are generally called wood rats. The rodents are numerous and include several peculiar species. Only one species of hare is found in Brazil, the Lepus brasiliensis, and but one also of the squirrel (Scyurus). Of the amphibious rodents, the prêá (Cavia aperea), mocó (C. rupestris), paca (Coelogenys paca), cutia (Dasyprocta aguti) and capybara (Hydrochoerus capybara) are noteworthy for their size and extensive range. Their flesh is used as an article of food, that of the paca being highly esteemed. Of the Muridae there are several genera and a large number of species, some of them evidently importations from the Old World. Brazil has three groups of animals similar to the common rat—the Capromydae, Loncheridae and Psammoryctidae—the best known of which is the “tuco-tuco” (Clenomys brasiliensis), a small burrowing animal of Rio Grande do Sul which excavates long subterranean galleries and lives on roots and bulbs. One of the characteristic orders of the Brazilian fauna is that of the Edentata, which comprises the sloth, armadillo and ant-eater. These animals are found only in the tropical regions of South America. The range of the sloth is from the Guianas south into Minas Geraes, the armadillo as far south as the Argentine pampas and the ant-eater from the Amazon south to Paraguay, though it is found in the Amazon region principally. The sloth (Bradypus) is an arboreal animal which feeds almost exclusively on the foliage of the Cecropias. It includes two recognized genera and half a dozen species, the best known of which is B. didactylus. The common name in Brazil is preguiça, which is equivalent to its English name. Of armadillos, commonly called tatú in Brazil, the largest species is the Dasypus gigas, but the best known is the tatú-été (D. octocinctus), which is highly esteemed for its flesh. The ant-eaters (Myrmecophaga) are divided into three or four species, one of which (M. jubata) is exclusively terrestrial, and the others arboreal. The popular name for the animal is tamanduá. The M. jubata, or tamanduá bandeira, is sometimes found as far south as Paraguay. Of the ruminants, Brazil has only four or five species of Cervidae, which are likewise common to other countries of South America. The largest of these is the marsh deer (C. paludosus), which in size resembles its European congeners. The others are the C. campestris, C. nemorivagus, C. rufus and a small species or variety called C. nanus by the Danish naturalist Dr P. W. Lund. The pachyderms are represented by three species of the peccary (Dicotyles) and two of the anta, or tapir (Tapirus). The former are found over a wide range of country, extending into Bolivia and Argentina, and are noted for their impetuous pugnacity. The tapir also has an extensive range between the coast and the foothills of the Andes, and from northern Argentina to south-eastern Colombia. It is the largest of the Brazilian mammals, and inhabits densely forested tracts near river courses. The two species are T. americanus, which is the larger and best known, and the anta chure, found in Minas Geraes, which is said to be identical with the T. Roulini of Colombia. Perhaps the most interesting mammal of Brazil is the manati, or sea-cow (Manatus americanus), which inhabits the lower Amazon and sometimes reaches a length of 15 to 20 ft. It is taken with the harpoon and its oil is one of the commercial products of the Amazon valley.

The avifauna of Brazil is rich in genera, species and individuals, especially in species with brilliantly-coloured plumage. It is estimated that more than half the birds of Brazil are insectivorous, and that more than one-eighth are climbers. The range in size is a wide one—from the tiny humming-bird to the ema, rhea, or American ostrich. Although the order which includes song-birds is numerous in species and individuals, it is noticeably poor in really good songsters. On the other hand it is exceptionally rich in species having strident voices and peculiar unmusical calls, like the pacô (Coracina scuttata) and the araponga (Chasmorhynchus nudicollis). Two species of vultures, twenty-three of falcons and eight of owls represent the birds of prey. The best known vulture is the common urubú (Cathartes foetens, Illig), which is the universal scavenger of the