High up the River Parana is found the magnificent waterfall, El Salto de Guira, rivalling in splendour Niagara itself. Other fine waterfalls are found on different rivers.
Here, too, the ant-eater reaches an enormous size. The capybara is also found. It is obliged to triturate its food—grass, and herbaceous plants—for a long time, in consequence of the contracted size of the oesophagus, which will hardly admit a goose-quill, although the animal is sometimes so large that it weighs more than two hundred pounds. Its destiny seems to be to feed jaguars, for they live principally on the creatures.
The chinchilla, another rodent, is very common in the fields and esteros. There is a large heron, called in Guarani the tuyùajù—that is, one which walks in the mud—nearly as tall as a man, with a bill more than a foot in length. The puma ranges throughout the country, as he does much further south; while the jaguar also appears amid the forests and plains.
Gregarious Spiders.
Among the insects, Masterman describes a gregarious spider which, when full-grown, has a black body half an inch in length—with a row of bright red spots on the side of the abdomen—four eyes, remarkably strong mandibles, and stout hairless legs an inch in length. They construct in concert huge webs, generally between two trees, ten or twelve feet from the ground. In a garden, among trees forty feet apart, these spiders had extended two long cables, as thick as pack-thread, to form the margin of each web, the lower being only four feet from the ground; and between them was a light, loose network perfectly divided into webs, each presenting about two square feet of surface. Each of these sub-webs was occupied by a spider from sunset to a little before sunrise. Six nets contained two thousand of the creatures. They often change their location; and a double stream was always passing along the cables, apparently strengthening them as they came and went.
Sometimes three or four would be lying in wait within a few inches of each other, the one crawling over or under the other’s body without hesitation. Soon after sunrise they left their webs, and, retreating to the shade, formed two or three large masses as big as a hat under the thick foliage of a jessamine-tree. There they remained motionless till sunset, when the black lump crumbled to pieces. The process was a curious sight to witness. Then, in a leisurely way, the spiders scattered themselves to their aerial fishing. The air swarmed with mosquitoes, which were caught in great numbers. Larger flies, and especially moths, were at once pounced upon and devoured; a dozen often feeding amicably on the body of the same insect, consuming not only the juices, but the abdomen. When a part of the web was broken, the nearest spider gathered up the loose threads, rolled them into a ball, and ate it. The great difficulty seemed to be how they could convey the first thread, often sixty or seventy feet long, from one tree to the other. This was done by a spider from a tree to windward forming a long line, which blew out and caught in the leaves of a neighbouring tree to leeward. This it tightened, and then crossed hastily backwards and forwards on the line, adding to its thickness on each journey, till it was strong enough to support a web. The spiders thus employed were apparently all young, for as they increased in age the ferocity of the race appeared. There was then a sanguinary battle,—the few survivors, probably females, devouring some of the slain to provide for a future brood, and then dying also.
The Chigo, or Sand-Flea.
Mr Masterman makes some interesting remarks on the chigo, or sand-flea (Pulex penetrans). It is very minute, not exceeding one twenty-fifth of an inch in length. It burrows between the cuticle and true skin, and there lays its eggs—producing a swelling containing a bluish white sac, about the tenth of an inch in diameter, filled with them. This sac is the developed abdomen of the flea. It preserves its vitality after the death of the rest of the parent; and when that event
takes place, the eggs are mere germs, which would ordinarily perish at the same time.