sometimes found in the head of the yguanà, which, when ground to powder, and drunk with a wholesome potion, or simply applied to the body, diminish or remove stone in the kidneys. Others affirm that a stone, an ounce in weight, is found in some other part of this animal's body, which, when reduced to powder, and drunk in tepid water, removes obstructions of the bladder. I never saw any stones of this kind—never tried their efficacy. Besides this, other kinds of lizards, of different forms and colours, are seen in Paraguay, but I have nothing remarkable to relate of them. The chameleon is very seldom seen here. I once saw one jump hastily out of a boat which lay on the ground near the shore, but had not time to examine it closely. RIVER-WOLVES. Many rivers, and even lesser streams, produce two kinds of wolves, a larger, and a smaller. Sometimes the Abiponian women tame the whelps at home, suckling them like their own children. They also do the same kind office for puppies, although no wife can suckle another person's child without greatly offending her husband, and running the risk of being divorced. These wolves are killed with various weapons by the Abipones, who, though their flesh is not fit for food, make use of their skins, which are of a dusky colour, but yellow at intervals, with extremely soft hair. SEALS. Seals are remarkable for the size of their bodies, and are very numerous in the river Plata, especially at the mouth by which it enters the sea. They have more fat than flesh, so that hunger alone could induce me to taste them. But their skin, of an elegant yellow colour, marked with a black line on the back, and covered with very soft hair, is much prized by Europeans. Our companions, who, at the command of King Philip the Fifth, sailed to the shores of Magellan, record that seals in that place often exceed a bullock two years old in size; that they often strive with one another on the sandy shore, lifting up their bodies as straight as a pillar, and that many geographers have erred in saying that these seals have a mane, and in giving them the name of sea-lions. This is no affair of mine; let others decide the point. I think the dispute is all about a name. FROGS AND TOADS.