"There are three kinds of howling monkeys in South America," said the Doctor, "but the difference is more observable in their appearance than in their voices. The braying of a mule is like the note of a violin, compared to the noise of a howling monkey in good health and condition, accompanied by his friends. The howlers, like most others of the Simian family, are gregarious, and if we happen to have our camp near a village of them we shall not sleep much." Frank thought he would buy one of these brutes and take him home, but Manuel said the howlers could not be tamed. "A wise provision of nature," remarked Fred. "Imagine your neighbor having a pet howler; it would be worse than all the cats in a dozen blocks of New York city." Frank agreed with him, and changed his views on the subject of domesticating one of these curiosities. Manuel said further that the natives had repeatedly tried to tame the howlers, but could not; they were the only members of the monkey family in South America that utterly refused to be converted into pets. They fell into the monkey-market sooner than they had expected. While passing an island, an hour or two before sunset, they saw two or three canoes drawn up on the shore, and at the Doctor's suggestion Manuel told the pilot to run in and see who and what the owners were. They proved to be a hunting-party of Indians from the other side of the river; they had been successful in killing several monkeys, and offered some of the meat for sale. Frank and Fred thought it would be too much like cannibalism to eat of monkey meat, and the Doctor agreed with them. Manuel said the flesh of the howler was not to be recommended, as it was dry and tough, but there were some varieties on the lower Amazon which were not to be despised. He particularly mentioned the white-whiskered coaita, one of the thumbless "spider-monkeys," which was held in high repute among the natives. Another variety called the maquisapa was said to be good eating, but he could not speak from personal knowledge. Monkey flesh is an important article of food in many parts of the Amazon valley, and there are certain districts where it is the only meat to be had. But monkey in its live form was not declined, at least in limited quantity. One of the Indians offered a marmoset, a pretty little creature about eight inches long, and with a soft, silky fur covering its skin. It was restless and timid; at first it shrank from the youth, but quickly seemed to understand that it would find him a better master than the Indian. He took it in his hand and gently stroked its back; in a few moments it clung to him, and when the Indian reached for his property the little creature struggled to remain.