"What happened to the monkey?" Fred asked. "I don't know exactly what became of him," was the reply. "He was given to one of the boatmen, who sold him to an Indian at the next landing. It wasn't safe to mention monkey to that gentleman for the rest of the time he stayed in the country." [Illustration: HUNTING THE MONKEY.] Sunset came, and they stopped for the night. The raft was tied up at a small island, where there was little prospect of disturbance by hostile Indians; the tribe occupying this part of the country did not have a bad reputation, and there was no real danger, but the pilot was cautious on general principles. Watch was kept through the night, but nothing happened to disturb the slumber of those whose duties did not require them to be wakeful, if we except the visits of the mosquitoes. Mosquitoes are the pests of the upper part of the entire valley of the Amazon. They are found wherever the rains fall, from the foot of the Andes, eastward, until within a few hundred miles of the Atlantic coast, from which they are kept in great measure, though not entirely, by the force of the trade winds. The middle Amazon swarms with them, and the Maranon, Madeira, and other tributaries are almost uninhabitable at certain seasons of the year, in consequence of these nuisances. They are always on duty, and no manner of objecting to their presence will induce them to leave. [Illustration: AMAZONIAN MOSQUITOES AT HOME.] There are several varieties of mosquitoes, some working at night, and others in the daytime; between them they divide the hours, and give their victim no chance for rest. The Indians say they always come in greater swarms than usual when a traveller is approaching, and evidently they can scent blood from afar. Frank said "the mosquitoes fairly danced with joy at the arrival of our party." A mass meeting was called, which was attended by some millions of mosquitoes, "very hungry and very thirsty." This mass meeting was kept up as long as they were in the region of the upper and middle Amazon. After passing Manaos, on their way down the river, there were few mosquitoes, and these few were not as voracious as their more uncivilized brethren. Parts of Brazil and Bolivia will long remain unsettled, owing to the perpetual annoyance caused by the mosquitoes. Their powers were tested by one traveller, Dr. Spruce, who, in the interest of science, allowed the insects to feed upon him without interruption, and found they took three ounces of blood daily! Our friends were provided with mosquito nettings, and brought them into use on entering the mosquito-haunted region. At night they surrounded their beds with them, and by day kept their heads enveloped in the small nets made for that purpose; in this way they managed to keep from being devoured bodily, or bled to death, but could not escape the annoyance and constant inconvenience of the presence of the dreaded carapana, as he is called by the Brazilians.