[AM] Sonnini says, that wishing to kill a sloth for the purpose of preparing the skin, he exhausted every possible means to deprive it of life; but such was its principle of vitality that he could not remain any longer a witness of his own barbarous endeavours; and he quitted the room seized with horror at the idea of the evils which this miserable animal must endure, and with astonishment at that impenetrability which prolonged its existence. Both these animals belong to the southern parts of the New Continent, and are never to be met with in the Old. We have already observed, that the editor of Seba's cabinet was deceived in calling the unau by the name of the _Ceylon sloth_. This error, which has been adopted by Klein, Linnæus, and Brisson, is now more evident than formerly. The Marquis de Montmirail has a living unau, which was brought him from Surinam: those in the royal cabinet came from the same place, and from Guiana; and I am persuaded, that both species exist in the desarts of America, from Brasil to Mexico; but as it never inhabited the northern countries, it could not have passed from one continent to the other; and if these animals have been seen either in the East Indies, or on the coast of Africa, it is certain, that they must have been transported thither. They can endure neither cold nor rain; the change from wet to dry spoils their fur, which then resembles bad dressed hemp, rather than wool or hair. I cannot conclude this article better than by inserting the observations which the Marquis de Montmirail communicated to me concerning the unau, which had been above three years in his menagerie. "The fur of the unau is much softer than that of the aï. It is probable that what travellers have said of the excessive slowness of the sloths, only belongs to the aï. The unau, although very heavy, and of an excessively aukward motion, ascends and descends the highest tree many times in a day: he is most active in the evening and during the night, which makes it probable that he sees but badly in the day, and that his eyes are of no use to him but in the dark. When I bought this animal at Amsterdam, it was fed with sea-biscuit, and I was told, that when the winter was over, and the verdure began to appear, it would require nothing but leaves. We supplied him with leaves which he ate freely while they were green and tender; but the moment they began to be dry, shrivelled, or worm-eaten, he refused them. During the three years that I preserved him in my menagerie, his common food was bread, apples, and roots; and his drink always milk. He always took his food in one of his fore-claws, but with difficulty, and which was increased in proportion to the size. His cry, though plaintive and melancholy, does not resemble that of the aï; it is short, and seldom uttered. The most natural situation of the unau, and which he prefers to all others, is suspending himself on a branch of a tree, with his body downwards. He