DISTRIBUTION.--Forests of Brazil, extending north into Mexico. Mr. Bates remarks in reference to this species: "I was surprised on my return to England to learn that the Pigmy Marmoset was found also in Mexico, no other Amazonian Monkey being known to wander far from the great river plain. Thus the smallest, and apparently the feeblest, species of the whole order is one which has by some means become the most widely dispersed." HABITS.--Little or nothing is known of the habits of this individual species, but there is very little doubt that they agree closely with those of the Common Marmoset. VII. THE BLACK-TAILED MARMOSET. HAPALE MELANURA. _Simia argentata_, Linn., Syst. Nat., p. 40 (1766), albino var. _Jacchus melanura_, Geoffr., Ann. Mus., xix., p. 120 (1812); Gray, P. Z. S., 1865, p. 734. _Jacchus argentatus_, Geoffr., t. c. p. 120. _Hapale melanura_ (nec Kuhl); Wagner in Schreb., Säugeth., i., p. 127, fig. 36 (1840), and Suppl. v., p. 15, fig. 13 (1855); Scl., P. Z. S., 1875, p. 419, pl. l.; Schl., Mus. Pays Bas, vii., p. 267 (1876). _Midas argentatus_, Bates, Nat. Amaz., i., p. 162 (1863). {137}_Mico melanurus_, Gray, Cat. Monkeys Brit. Mus., p. 64 (1870). _Hapale argentata_, Schl., Mus. Pays Bas, vii., p. 268 (1876). CHARACTERS.--Face naked, flesh-coloured; ears naked, flesh-coloured, exposed; no ear-pencils, as in _H. chrysoleuca_; tail uniform black; head and fore-limbs pale brown; front of the body paler; front edges of the thighs, and a band across the loins, white. Length, 7 inches, without the tail. Some varieties have the body entirely covered with long, white, silky hairs. DISTRIBUTION.--Bolivia and Brazil. Mr. Bates says that the Black-tailed Marmoset is one of the rarest of the American Monkeys. He did not hear of its being found anywhere in Amazonia except near Cametá, on the River Tocantins. HABITS.--Little is known of the habits of this species, few naturalists having had the good fortune to observe it in its native state. Mr. Bates, however, once saw three individuals together, running along a branch, and looking like white Kittens. "I afterwards saw a pet animal," he says in his book, "of this species, and heard that there were many so kept, and that they were esteemed as choice treasures.... It was a most timid and sensitive thing. The woman who owned it carried it constantly in her bosom, and no money would induce her to part with her pet.... The nervous little creature would not permit strangers to touch it. If anyone attempted to do so, it shrank back, the whole body trembling with fear, and its teeth chattered, whilst it uttered its tremulous, frightened tones. The expression of its features was like that of its more robust brother, _Midas ursulus_; the eyes, which were black, were full of curiosity and mistrust, and it always kept them fixed on the person who attempted to advance towards it." {138}THE TAMARINS. GENUS MIDAS. _Midas_, Geoffr., Ann. Mus., xix., p. 120 (1812).