At the head of the amphibious animals stands the crocodile, which exceeds all the rest in the slowness of its motions, and the size of its body. The young creature, when it breaks its shell, resembles a small lizard, such as is commonly seen in European gardens, scarce more than half a span in length. In the course of years it grows by degrees to an enormous size. Crocodiles ten feet long are very common in Paraguay. When a two years' drought had exhausted many of the lakes and rivers in Paraguay, among other aquatic beasts we found numbers of crocodiles roaming about the plain, which died of thirst from being unable to get a sufficiency of water. I am of opinion that most crocodiles reach to extreme old age from the advantage of a singular nature, by which they are so effectually fortified, that it is exceedingly difficult to kill them. I will give you a description of this animal. It has a large, flat head, a very wide mouth, armed on each side with extremely sharp, but unequal teeth, and large, round grey eyes, with a black pupil. It has no tongue, but the place of one is supplied by a little immoveable membrane. Its feet, which are furnished like birds' claws with four fingers, and nails, it uses, sometimes in walking slowly on the shore, sometimes in swimming. Its body, which resembles a huge trunk, terminates in a long tail, like the point of a weapon, at the extremity of which lies a small black ball, closed on every side, the distinguishing mark of the female sex, for the males are not furnished with this ball. Its rough skin, covered with very hard scales, which are elegantly variegated with black and white, like shells, forms a mail which renders its head, back and tail impenetrable to all weapons. Softer scales adorn rather than arm its belly, sides and feet, where circular or square figures, distinguished at intervals by a colour partly yellow, partly dusky, project, like shells, from the surface of the skin. The tail is composed of blackish rings, and a little denticulated fin which it moves in swimming. The skin of the neck is softer, and very easily wounded. Crocodiles on being attacked by tigers, kill them by a stroke of their tail. They are themselves killed if their neck or belly, both which are covered with softer skin, is wounded by the horns or claws of beasts, by a bullet, a spear, or an arrow; on these occasions they take to swimming, but the Indians generally swim after them, and bring them back to shore. During a pretty violent south wind crocodiles are rendered torpid by the cold at night, from being immersed in pools; but when the sun is risen, they lie, like logs of wood, on the sunny shore to warm themselves, and their limbs being stiffened, and their senses almost gone, are pierced with spears by the Abipones, without danger or trouble. Leaving their bodies, they carry away nothing but the teeth, and the little bones of the spine, which, being as hard as iron, as sharp as awls, and at the same time elastic,