ber of discoloured punctures that are crowded together. The irritation they produce is more acutely felt by some persons than others. I once travelled with a middle-aged Portuguese, who was laid up for three weeks from the attacks of Piúm; his legs being swelled to an enormous size, and the punctures aggravated into spreading sores.[1]
A brisk wind from the east sprang up early in the morning of the 22nd: we then hoisted all sail, and made for the mouth of the Rio Negro. This noble stream at its junction with the Amazons, seems, from its position, to be a direct continuation of the main river, whilst the Solimoens which joins at an angle and is somewhat narrower than its tributary, appears to be a branch instead of the main trunk of the vast water-system. One sees therefore at once, how the early explorers came to give a separate name to this upper part of the Amazons. The Brazilians have lately taken to applying the convenient term Alto Amazonas (High or Upper Amazons), to the Solimoens, and it is probable that this will gradually prevail over the old name. The Rio Negro broadens considerably from its mouth upwards, and presents the appearance of a great lake; its black-dyed waters having no current, and seeming to be dammed up by the impetuous flow of the yellow, turbid Solimoens, which here belches forth a continuous line of uprooted trees
- ↑ The Piúm belongs probably to the same species as the Mosquito of the Orinoco, described by Humboldt, and which he referred to the genus Simulium, several kinds of which inhabit Europe. Our insect is nearly allied to Simulium, but differs from the genus in several points, chiefly in the nervures of the wings.
