On the 28th of March I was on the river bank trying to measure the width of the Apure river, which was 206 toises. It was thundering everywhere; the first storm and rains of the rainy season. The river was whipped up by an east wind into large waves, then it suddenly calmed down, and then many large cetaceans, resembling the dolphins of our seas, began to play in long lines on the river surface. The slow and lazy crocodiles seemed to fear these noisy and impetuous animals as they dived underwater when these animals approached. It is extraordinary to find these mammals so far from the coast. The mission Spaniards call them toninas, as they do dolphins; their Tamanaco name is orinucna. They are 3 to 4 feet long, and on bending their backs and whipping the water with their tails they reveal part of their back and dorsal fins. I did not succeed in catching any of them, though I often paid Indians to shoot at them with arrows.