In this extract the author refers to a memoir previously published by himself, in the “Commentarii” of the Academy of St. Petersburg. This memoir, written in Latin, and entitled “Upon some Animals of Siberia,” has never been translated. After some general considerations, the author thus relates the circumstances attending the discovery of the fossil Rhinoceros, with some official documents affirming their correctness, and the manner in which the facts were brought under his notice by the Governor of Irkutsk, General Bril: “The skin and tendons of the head and feet still preserved considerable flexibility, imbued as it were with humidity from the earth; but the flesh exhaled a fetid ammoniacal odour, resembling that of a latrine. Compelled to cross the Baïkal Lake before the ice broke up, I could neither draw up a sufficiently careful description nor make sketches of the parts of the animal; but I made them place the remains, without leaving Irkutsk, upon a furnace, with orders that after my departure they should be dried by slow degrees and with the greatest care, continuing the process for some time, because the viscous matter which incessantly oozed out could only be dissipated by great heat. It happened, unfortunately, that during the operation the posterior part of the upper thigh and the foot were burnt in the overheated furnace, and they were thrown away; the head and the extremity of the hind foot only remained intact and undamaged by the process of drying. The odour of the softer parts, which still contained viscous matter in their interior, was changed by the desiccation into one resembling that of flesh decomposed in the sun. “The Rhinoceros to which the members belonged was neither large for its species nor advanced in age, as the bones of the head attest, yet it was evidently an adult from the comparison made of the size of the cranium as compared with that of others of the same species more aged, which were afterwards found in a fossil state in divers parts of Siberia. The entire length of the head from the upper part of the nape of the neck to the extremity of the denuded bone of the jaw was thirty inches; the horns were not with the head, but we could still see evident vestiges of two horns, the nasal and frontal. The front, unequal and a little protuberant between the orbits, and of a rhomboidal egg-shape, is deficient in the skin, and only covered by a light horny membrane, bristling with straight hairs as hard as horn.