_Cebus chrysopes_ (Le Sajou à pieds dorés), Fr. Cuv., Hist. Nat. Mammif., pl. 51 (part.). _Cebus albifrons_, Is. Geoffr., Ann. Mus., xix., p. 111 (1812); Gray, Cat. Monkeys Brit. Mus., p. 50 (1870); Schl., Mus. Pays Bas, vii., p. 195 (1876, part.) _Cebus leucocephalus_, Gray, t. c. p. 50. _Cebus versicolor_, Pucher., Rev. Zool., 1845, p. 335 (part). {214}CHARACTERS.--Head large in proportion to the body. Hair of crown short, reflexed, without crest or "horns." Tail with rather long hair. Face, forehead, throat, shoulders, and crest white. General colour of body light or reddish-brown; back and outer side of the limbs, brownish-red. DISTRIBUTION.--Generally distributed through the forests of the level country of the Upper Amazon. HABITS.--The Caiarara, as the Tupi Indians name this species, lives in troops in the forests and feeds on fruits. Mr. Bates, who kept one in captivity for a considerable period during his stay in the Upper Amazon region, describes it as "a most restless creature, but not playful like most of the American Monkeys; the restlessness of its disposition seeming to arise from great nervous irritability and discontent. The anxious, painful, and changeable expression of its countenance, and the want of purpose in its movements, betray this. Its actions are like those of a wayward child; it does not seem happy even when it has plenty of its favourite food, bananas; but will leave its own meal to snatch the morsels out of the hands of its companions. It differs in these mental traits from its nearest kindred, for another common _Cebus_, found in the same parts of the forest, the Prego Monkey (_C. cirrifer_), is a much quieter and better tempered animal.... The Caiarara [called Ouavapavi, by Humboldt] is always making some noise or other, often screwing up its mouth and uttering a succession of loud notes resembling a whistle." It is the most wonderful leaper of the whole tribe. Mr. Bates has also recorded:--"The troops consist of thirty or more individuals which travel in single file. When the foremost of the flock reaches the outermost branch of an unusually lofty tree he springs forth {215}into the air without a moment's hesitation and alights on the dome of yielding foliage belonging to the neighbouring tree, maybe fifty feet beneath; all the rest following the example. They grasp, on falling, with hands and tail, right themselves in a moment, and then away they go along branch and bough to the next tree." Mr. Belt also mentions having kept a White-fronted Capuchin in captivity for a long time. Its actions, he tells us, were very human-like. "He had quite an extensive vocabulary of sounds, varying from a gruff bark to a shrill whistle; and we could tell by them, without seeing him, when it was he was hungry, eating, frightened, or menacing; doubtless one of his own species would have understood various minor shades of intonation and expression that we, not