Carved Figures on rocks, which form a belt running east and west from the Rupunuri, Essequibo, and mountains of Pacaraima, to the solitudes of the Cassiquiare. Earliest observation (April, 1749) of such traces of an ancient civilization, in the unpublished travels of the Surgeon Nicolas Hortsmann, of Hildesheim, found among d’Anville’s papers—pp. 147–151. The vegetable poison Curare, or Urari—pp. 151–152. ON THE CATARACTS OF THE ORINOCO, NEAR ATURES AND MAYPURES pp. 153–173. The Orinoco, general view of its course. Ideas excited in the mind of Columbus on beholding its mouth. Its unknown sources lie to the east of the lofty Duida and of the thickets of Bertholletia. Cause of the principal bends of the river—pp. 153–162. The Falls. Raudal of Maypures, bounded by four streams. Former state of the region. Insular form of the rocks Keri and Oco. Grand spectacle displayed on descending the hill Manimi. A foaming surface, several miles in extent, suddenly presents itself to view. Iron-black masses of tower-like rocks rise precipitately from the bed of the river; the summits of the lofty palms pierce through the clouds of vapoury spray—pp. 162–168. Raudal of Atures, another island-world. Rock-dykes, connecting one island with the other. They are the resort of the pugnacious, golden-coloured rock manakin. Some parts of the river-bed in the cataracts are dry, in consequence of the waters having formed for themselves a channel through subterranean cavities. Visit to these parts on the approach of night, during a heavy thunder-storm. Unsuspected propinquity of crocodiles—pp. 168–171. The celebrated cave of Ataruipe, the grave of an extinct tribe—pp. 171–173. SCIENTIFIC ILLUSTRATIONS AND ADDITIONS pp. 174–190. Abode of the river-cow (_Trichecus Manati_) in the sea, at the spot where, in the Gulf of Xagua on the southern coast of the Island of Cuba, springs of fresh water gush forth—pp. 174, 175. Geographical illustration of the sources of the Orinoco—pp. 175–179. Juvia (_Bertholletia_), a Lecythidea, remarkable as an instance of lofty organic development. Haulm of an Arundinaria upwards of sixteen feet from joint to joint—pp. 179–180. On the fabulous Lake Parime—pp. 180–188. The Parrot of Atures, a poem by Ernst Curtius. The bird lived in Maypures, and the natives declared that he was not understood, because he spoke the language of the extinct Aturian tribe—pp. 188–190. NOCTURNAL LIFE OF ANIMALS IN THE PRIMEVAL FOREST pp. 191–201.