The Amazon is a crowded aquarium, holding representatives of every zoological class—infusoria, hydras, fresh-water shells (chiefly Ampullaria, Melania, and Unios), aquatic beetles (belonging mostly to new genera), fishes, reptiles, water birds, and cetaceans. The abundance and variety of fishes are extraordinary; so also are the species. This great river is a peculiar ichthyic province, and each part has its characteristics. According to Agassiz, the whole river, as well as its tributaries, is broken up into numerous distinct fauna.[170] The pirarucú, or "redfish" (the Sudis gigas of science), is at once the largest, most common, and most useful fish. The Peruvian Indians call it payshi. It is a powerful fish, often measuring eight feet in length and five in girth, clad in an ornamental coat-of-mail, its large scales being margined with bright red. It ranges from Peru to Pará. It is usually taken by the arrow or spear. Salted and dried, the meat will keep for a year, and forms, with farina, the staple food on the Amazon. The hard, rough tongue is used as a grater. Other fishes most frequently seen are the prettily-spotted catfish, Pescada, Piranha, Acará, which carries its young in its mouth, and a long, slender needle-fish. There are ganoids in the river, but no sturgeons proper. Pickerel, perch, and trout are also wanting. The sting-ray represents the shark family. As a whole, the fishes of the Amazon have a marine character peculiarly their own.
The reptilian inhabitants of this inland sea are introduced by numerous batrachians, water-snakes (Heliops), and anacondas. But alligators bear the palm for ugliness, size, and strength. In summer the main river swarms with them; in the wet season they retreat to the interior lakes and flooded forests. It was for this reason that we did not see an alligator on the Napo. At low water they are found above the entrance of the Curaray. About Obidos, where many of the pools dry up in the fine months, the alligator buries itself in the mud, and sleeps till the rainy season returns. "It is scarcely exaggerating to say (writes Bates) that the waters of the Solimoens are as well stocked with large alligators in the dry season as a ditch in England is in summer with tadpoles." There are three or four species in the Amazon. The largest, the Jacaré-uassú of the natives, attains a length of twenty feet. The Jacaré-tinga is a smaller kind (only five feet long when full grown), and has the long, slender muzzle of the extinct teleosaurus. The South American alligators are smaller than the crocodiles of the Nile or Ganges, and they are also inferior in rank. The head of the Jacaré-uassú (the ordinary species) is broad, while the gavial of India has a long, narrow muzzle, and that of the Egyptian lizard is oblong. The dentition differs: while in the Old World saurian the teeth interlock, so that the two jaws are brought close together, the teeth in the upper jaw of the Amazonian cayman pass by the lower series outside of them. The latter has therefore much less power. It has a ventral cuirass as well as dorsal, and it is web-footed, while the crocodile has the toes free—another mark of inferiority. Sluggish on land, the alligator is very agile in its element. It never attacks man when on his guard, but it is cunning enough to know when it may do this with safety. It lays its eggs (about twenty) some distance from the river bank, covering them with leaves and sticks. They are larger than those of Guayaquil, or about four inches long, of an elliptical shape, with a rough, calcareous shell. Negro venders sell them cooked in the streets of Pará.
Turtles are, perhaps, the most important product of the Amazon, not excepting the pirarucú. The largest and most abundant species is the Tortaruga grande. It measures, when full grown, nearly three feet in length and two in breadth, and has an oval, smooth, dark-colored shell. Every house has a little pond (called currúl) in the back yard to hold a stock of turtles through the wet season. It furnishes the best meat on the Upper Amazon. We found it very tender, palatable, and wholesome; but Bates, who was obliged to live on it for years, says it is very cloying. Every part of the creature is turned to account. The entrails are made into soup; sausages are made of the stomach; steaks are cut from the breast; and the rest is roasted in the shell.[171] The turtle lays its eggs (generally between midnight and dawn) on the central and highest part of the plaias, or about a hundred feet from the shore. The Indians say it will lay only where itself was hatched out. With its hind flippers it digs a hole two or three feet deep, and deposits from eighty to one hundred and sixty eggs (Gibbon says from one hundred and fifty to two hundred). These are covered with sand, and the next comer makes another deposit on the top, and so on until the pit is full. Egg-laying comes earlier on the Amazon than on the Napo, taking place in August and September. The tracajá, a smaller species, lays in July and August; its eggs are smaller and oval, but richer than those of the great turtles.
The mammoth tortoise of the Galápagos lays an egg very similar in size and shape to that of the Tortaruga, but a month later, or in October. The hunting of turtle eggs is a great business on the Amazon. They are used chiefly in manufacturing oil (mantéca) for illumination. Thrown into a canoe, they are broken and beaten up by human feet; water is then poured in, and the floating oil is skimmed off, purified over the fire in copper kettles, and finally put up in three-gallon earthen jars for the market. The turtles are caught for the table as they return to the river after laying their eggs. To secure them, it suffices to turn them over on their backs. The turtles certainly have a hard time of it. The alligators and large fishes swallow the young ones by hundreds; jaguars pounce upon the full-grown specimens as they crawl over the plaias, and vultures and ibises attend the feast. But man is their most formidable foe. The destruction of turtle life is incredible. It is calculated that fifty millions of eggs are annually destroyed. Thousands of those that escape capture in the egg period are collected as soon as hatched and devoured, "the remains of yolk in their entrails being considered a great delicacy." An unknown number of full-grown turtles are eaten by the natives on the banks of the Marañon and Solimoens and their tributaries, while every steamer, schooner, and little craft that descends the Amazon is laden with turtles for the tables of Manáos, Santarem, and Pará. When we consider, also, that all the mature turtles taken are females, we wonder that the race is not well-nigh extinct. They are, in fact, rapidly decreasing in numbers. A large turtle which twenty years ago could be bought for fifty cents, now commands three dollars. One would suppose that the males, being unmolested, would far outnumber the other sex, but Bates says "they are immensely less numerous than the females." The male turtles, or Capitaris, "are distinguishable by their much smaller size, more circular shape, and the greater length and thickness of their tails." Near the Tapajos we met a third species, called Matá-matá. It has a deeply-keeled carapax, beautifully bossed, and a hideous triangular head, having curious, lobed, fleshy appendages, and nostrils prolonged into a tube. It is supposed to have great virtues as a remedy for rheumatism. But the most noticeable feature of the Amazonian fauna, as Agassiz has remarked, is the abundance of cetaceans through its whole extent. From the brackish estuary of Pará to the clear, cool waters at the base of the Andes, these clumsy refugees from the ocean may be seen gamboling and blowing as in their native element. Four different kinds of porpoises have been seen. A black species lives in the Bay of Marajó. In the Middle Amazon are two distinct porpoises, one flesh-colored;[172] and in the upper tributaries is the Inia Boliviensis, resembling, but specifically different from the sea-dolphin and the soosoo of the Ganges. "It was several years (says the Naturalist on the Amazon) before I could induce a fisherman to harpoon dolphins (Boutos) for me as specimens, for no one ever kills these animals voluntarily; the superstitious people believe that blindness would result from the use of the oil in lamps." The herbivorous manati (already mentioned, Chap. XV.) is found throughout the great river. It differs slightly from the Atlantic species. It rarely measures over twelve feet in length. It is taken by the harpoon or nets of chambiri twine. Both Herndon and Gibbon mention seals as occurring in the Peruvian tributaries; but we saw none, neither did Bates, Agassiz, or Edwards. They probably meant the manati.
[CHAPTER XXI.]
Life around the Great River.— Insects.— Reptiles.— Birds.— Mammals.
The forest of the Amazon is less full of life than the river. Beasts, birds, and reptiles are exceedingly scarce; still there is, in fact, a great variety, but they are widely scattered and very shy. In the animal, as in the vegetable kingdom, diversity is the law; there is a great paucity of individuals compared with the species.[173] Insects are rare in the dense forest; they are almost confined to the more open country along the banks of the rivers. Ants are perhaps the most numerous. There is one species over an inch long. But the most prominent, by their immense numbers, are the dreaded saübas. Well-beaten paths branch off in every direction through the forest, on which broad columns may be seen marching to and fro, each bearing vertically a circular piece of leaf. Unfortunately they prefer cultivated trees, especially the coffee and orange. They are also given to plundering provisions; in a single night they will carry off bushels of farina. They are of a light red color, with powerful jaws. In every formicarium or ant colony there are three sets of individuals—males, females, and workers; but the saübas have the singularity of possessing three classes of workers. The light-colored mounds often met in the forest, sometimes measuring forty feet in diameter by two feet in height, are the domes which overlie the entrances to the vast subterranean galleries of the saüba ants. These ants are eaten by the Rio Negro Indians, and esteemed a luxury; while the Tapajos tribes use them to season their mandioca sauce. Akin to the vegetable-feeding saübas are the carnivorous ecitons, or foraging ants, of which Bates found ten distinct species. They hunt for prey in large organized armies, almost every species having its own special manner of marching and hunting. Fortunately the ecitons choose the thickest part of the forest. The fire-ant is the great plague on the Tapajos. It is small, and of a shiny reddish color; but its sting is very painful, and it disputes every fragment of food with the inhabitants. All eatables and hammocks have to be hung by cords smeared with copaiba balsam.