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.