Potamians, or River Tortoises.
The River Tortoises live constantly in the water, only coming to land occasionally; they swim with much ease below and on the surface. The carapace is very broad and flat; the toes united up to the claws by broad flexible membranes. These membranes change the feet into true paddles, which perform the office of oars. They seem to attain a considerable size, one kept by Pennant for three months weighing twenty pounds, its buckler not reckoned; the neck measuring twenty inches in length. The upper parts of their bodies vary in tint from brown to grey, with irregularly marbled, dotted, or ocellated spots; the underpart is a pale white, rosy, or purple tint. Sinuous brown, black, or yellow lines are symmetrically disposed on the right and left, principally on the neck and on the limbs.
During the night, when they think themselves safe, the River Tortoises seek repose on the rocks and islets, or on timber floating in the rivers, from which they plunge into the water on the slightest noise. These Tortoises, which accommodate themselves so perfectly to the medium that they inhabit, are continually at war with the fishes, reptiles, mollusks, and other denizens of the rivers. They are voracious and active, and are relentless enemies to the young of fishes, and especially of Crocodiles.
The carapace of the River Tortoise, Trionyx, is soft, covered with a flexible cartilaginous skin resting on a greatly-depressed osseous disk; its upper surface is covered with shrivelled sinuosities. As they are destitute of scales these Tortoises are said to be soft; their flesh is much esteemed, and they are angled for with hook and line, baited with small fishes or living worms and mollusks, or with dead bait, to which the sportsman gives motion and apparent life, for they are said never to approach dead prey. When they seize their victim, or defend themselves, they dart out their head and long neck with great rapidity, biting sharply with their trenchant beak, and holding on till they have bitten out the piece. From this peculiarity they are commonly known in the United States as the Snapping Turtle. Persons wading have been known to lose toes from their bite.
Fig. 39.—Trionyx Ægyptiacus.
M. Lesueur states that towards the beginning of May the females of Gymnopus spinifera, belonging to this division, seek out sunny sandy spots on the river's bank for the deposit of their eggs; they are not deterred from choosing steeps of ten or fifteen feet for this purpose. Their eggs are spherical, and more fragile than those of the Marsh Tortoise. They deposit from fifty to sixty at a time. None of this group are found in Europe. The fresh-water lakes and rivers of the warmer regions, such as the Nile and the Niger, in Africa, the Mississippi, the Ohio, and the Amazon rivers, in America, the Euphrates and the Ganges, in Asia, are its habitats. Among other remarkable species in the group we here represent Trionyx Ægyptiacus, [Fig. 39], supposed to be the Εμυς of Aristotle.
No modern naturalist has done more to illustrate the habits of the Fresh-water Turtle than Mr. Bates, in his highly interesting work, "The Naturalist on the Amazon." "The great Fresh-water Turtle (probably Platemys æfipes) of the Amazon or Solimoens grows on the upper river," he says, "to an immense size, a full-grown one measuring nearly three feet in length, by two in breadth, and is a load for the strongest Indian. Every house (in Ega) has a little pond called a corral, or pen in the back-yard, to hold a stock of these animals through the season of dearth—the wet months. Those who have a number of Indians in their employ send them out for weeks, when the waters are low, to collect a stock, and those who have not purchase their supply—this is attended with some difficulty however, as they are rarely offered for sale. The price of Turtles, like that of other articles of food, has risen greatly since the introduction of steam-vessels. Thus, when I arrived, in 1850, a middle-sized one could be bought for ninepence, but when I left, in 1859, they were with difficulty obtained for eight or nine shillings each. The abundance of Turtles varies with the amount of diurnal subsidence of the waters. When the river sinks less than the average, they are scarce; but when high waters have prevailed, they can be caught in abundance, their haunts being less restricted, and appropriate breeding-places more numerous.
"The flesh is very tender, palatable, and wholesome; but it is very cloying, and every one ends sooner or later by becoming thoroughly surfeited. I became so sick of Turtle in the course of two years that I could not bear the smell of it, although nothing else was to be had; consequently I suffered from actual hunger."
One of the most amusing sketches in Mr. Bates' book is a journey he made on the Solimoens, during which he visited the praias, or sand-islands, the Turtle-pools in the forests, and the by-streams and lakes of the great river. His companion was Cardozo, who was a sort of official superintendent of the diggers for Turtles' eggs on the sand-banks of Shimuni, the island lying nearest to Ega. There are four or five of these Royal Praias, as they are called, in the district, each having its commandant, whose business is to see that every inhabitant has an equal chance in the egg-field.
"The pregnant Turtles descend from the interior pools of the main river in July and August, before the outlets dry up, and seek their favourite sand-island in countless swarms; for it is only a few praias that are selected by them out of the great number existing. When hatched, the young animals remain in the pools throughout the dry season; for these breeding-places of the Turtle then lie from twenty to thirty feet above the level of the river, and are accessible only by cutting a path through the dense forest." On the 26th of September Mr. Bates left Ega with his companion, who was about to visit the sentinels placed to mark when and where the Turtles laid their eggs. Their conveyance was a stoutly-built canoe, or igareté, arranged for two paddlers, with an arched covering in the stern, under which three persons could sleep pretty comfortably. The swift current of the Solimoens carried them rapidly to the large wooded island of Baria, which divides the river into two broad channels. Shimuni lies in the middle of the north-easterly passage. They were quickly paddled across, reaching it an hour before sunset. The island is about three miles long and half a mile broad. The forest which covers it rises to an immense uniform height, presenting all round a compact and impervious front, the uniformity being interrupted here and there by a singular tree, called Mulatto wood, whose polished dark-green trunk is seen conspicuously through the mass of vegetation. The sand-bank lies at the upper end of the island, and extends several miles, presenting an irregular surface of ridges and hollows. At the further shore to the north-east, where no forest line shuts out the view, the white, rolling, sandy plain stretches away to the horizon; to the south-west a channel, about a mile in breadth, separates Baria from Shimuni.
Arrived at this island, Mr. Bates proceeds to describe with great minuteness the operations of the Turtles, as well as those of the sentinels placed to watch them.
"We found two sentinels," he says, "lodged in a corner of the praia, where it commences at the foot of the towering forest west of the island, having built themselves a little rancho with poles and palm-leaves. Great precautions are obliged to be taken to avoid disturbing the vigilant Turtles, which, previous to crawling ashore to lay, assemble in great shoals off the sand-bank. The men during this time take care not to show themselves, and they warn off any fisherman who attempts to pass near the place; for the passage of a boat, or the sight of a man, or a fire on the sand-bank, would prevent their laying their eggs that night, and if repeated, they would forsake the praia for some quieter place."
After a night spent under a temporary shed rapidly constructed for himself and companion, Mr. Bates rose from his hammock shivering with cold.
"Cardoza and the men were already watching the Turtles on a stage erected on a tall tree fifty feet high; from this watch-tower they are enabled to ascertain the place and date of successive deposits of eggs, and thus guide the commandant in fixing the time for his general invitation to the Ega people. The Turtles lay their eggs during the night, leaving the water in vast crowds when all around is quiet, when they crawl to the central and highest part of the praia. The hours between midnight and dawn are those when the Turtles excavate, with their broad, webbed paws, deep holes in the fine sand, the animal in each case making a pit about three feet deep; in this pit it lays its eggs, about a hundred and twenty in number, covering them over with sand; then a second deposit is placed on the top of the first, and so on until the pit is full." This goes on for about fourteen days. "When all have done, the area, or taboliero, over which they have been digging is only distinguished from the rest of the praia by signs of the sand having been a little disturbed.
"On rising I went to join my friends," he continues, "and few recollections of my Amazonian rambles are more vivid and agreeable than that of my walk over the white sea of sand on this cool morning. The sky was cloudless; the just-risen sun was hid behind the dense woods on Shimuni, but the long line of forest to the west on Baria, with its plumy decorations of palms, was lighted up with his yellow horizontal rays. A faint chorus of singing-birds reached the ears from across the water, and flocks of Gulls and Plovers were calling plaintively over the swelling banks of the praia. Tracks of stray Turtles were visible on the smooth white surface, two of which had been caught, for stragglers from the main body are a lawful prize.
"On arriving at the edge of the forest I mounted the sentinels' stage just in time to see the Turtles retreating to the water on the opposite side of the sand-bank. The sight was well worth the trouble of ascending. They were about a mile off, but the surface of the sand was blackened with the multitudes which were waddling towards the river; the margin of the praia was rather steep, and they all seemed to tumble head first down the declivity into the water."
On the 2nd of October the same party left Ega on a second excursion, the object of Cardoza being this time to search certain pools in the forest for young Turtles. The exact situation of these hidden sheets of water are known to few. The morning was cloudy and cool, and a fresh wind blew down the river; they had to struggle, therefore, against wind and current. The boat was tossed about and shipped a good deal of water. Their destination was a point of land twenty miles below Shimuni. The coast-line was nearly straight for many miles, and the bank averaged about thirty feet above the then level of the river; at the top rose an unbroken hedge of forest. No one could have divined that pools of water existed on that elevated land.
A path was cut through the forest by our party with their hunting-knives to the pool, half a mile distant; short poles were cut and laid across the path, over which three light canoes were rolled, after being dragged up the bank. A large net, seventy yards in length, was then disembarked and carried to the place. Netting, however, the older Indians considered unsportsmanlike; and, on reaching the pool, they commenced shooting the Turtles with bows and arrows from light stages erected on the shores.
"The pool covered an area of about four acres, and was closely hemmed in by the forest, which, in picturesque variety and grouping, often exceeded almost anything I had seen. The margins for some distance were swampy, and covered with large tufts of fine grass called matupá. These tufts were in many places overrun with ferns, and exterior to them was a crowded row of arborescent shrubs growing to a height of fifteen or twenty feet, forming a green palisade. Around the whole stood the taller forest trees—palmate-leaved Cecropiæ; slender Assai palms thirty feet high, with their thin feathery heads crowning their gently-curving, smooth stems; and, as a background to these airy forms, lay the voluminous masses of ordinary forest trees, with garlands, festoons, and streamers of leafy parasites hanging from their branches."
The pool which was hemmed in by this gorgeous scenery was nowhere more than five feet deep, and of that one foot was a fine soft mud. Cardoza and the author spent an hour paddling about admiring the skill displayed by the Indians in shooting Turtles. They did not wait for the animals to come to the surface to breathe, but watched for the slightest movements in the water which revealed their presence underneath; that instant an arrow flew from the bow of the nearest man, which never failed to pierce the shell of the submerged animal, and by mid-day about a score of full-grown Turtles had been shot. The net was now spread at one extremity of the oval-shaped pool, its side resting on the bottom, while the floats buoyed the other side up on the surface, the cords being held by two Indians. The rest of the party now spread themselves round the pool, beating the water with long poles, in order to drive the Turtles towards the centre. When they neared the net, the men moved more quickly, beating and shouting with great vigour. The ends of the net were now seized with vigorous hands, and dragged suddenly forward, bringing them at the same time together, so as to enclose all within a circle. Every man then leapt into the enclosure, the boats were brought up, and the captured Turtles were thrown in. In this manner about eighty were secured in twenty minutes.
Among these were several male Turtles, or capetaris, as they are called by the natives. They are much less numerous than the females, much smaller, and more circular in shape; their flesh is considered unwholesome.
On the 17th of October, the day announced for the taboliero, or egg-digging, Mr. Bates made a last excursion in Senhor Cardoza's company. Egg-collecting occupied four days. On the morning of the 17th about four hundred persons were assembled on the sand-bank; each family had erected a rude temporary shed of poles and palm-leaves, to protect themselves from sun and rain. Large copper kettles to prepare the oil, and hundreds of red earthenware jars, were scattered about on the sands. The commandant commenced by taking down the names of all masters of households, with the number of persons each intended to employ in digging; he then exacted from each a fine equal to fourpence a head towards defraying the expense of the sentinels, when the whole were allowed to go to the taboliero. It was exhausted by the end of the second day, when each household had erected large mounds of eggs beside their temporary hut.