A most curious fact connected with this monkey is the existence of an allied form, or brother species, in a tract of country lying to the west of its district. ‘This differs in being clothed with red instead of white hair, and has been described by Isidore Geoffroy St. Hilaire (from specimens brought to Paris in 1847 by the Comte de Castelnau) as a distinct species, under the name of Brachyurus rubicundus. It wholly replaces the white form in the western parts of the Japura delta: that is to say, in a uniform district of country, 150 miles in length, and sixty to eighty in breadth, the eastern half is tenanted exclusively by white Uakaris, and the western half by red ones. ‘The district, it may be mentioned, is crossed by several channels, which at the present time doubtless serve as barriers to the dispersal of monkeys, but cannot have done so for many centuries, as the position of low alluvial lands, and the direction of channels in the Amazons Valley, change considerably in the course of a few years. The red-haired Uakari appears to be most

frequently found in the forests lying opposite to the mouth of the river which leads to Fonteboa, and ranges thence to the banks of the Uati-parana, the most westerly channel of the Japurd, situated near Tunantins. Beyond that point to the west there is no trace of either the red or the white form, nor of any other allied species. Neither do they pass to the eastward of the main mouth of the Japurd, or to the south shore of the Solimoens. How far they range northwards along the banks of the Japura, I could not precisely ascertain; Senhor Chrysostomo, however, assured me that at 180 miles from the mouth of this river, neither white nor red Uakari is found, but that a third, black-faced and gray-haired species takes their place. I saw two adult individuals of Brachyurus rubicundus at Ega, and a young one at Fonteboa; but was unable to obtain specimens myself, as the forests were inundated at the time I visited their locality. I was surprised to find the hair of the young animal much paler in colour than that of the adults, it being of a sandy and not of a brownish-red hue, and consequently did not differ very much from that of the white species; the two forms, therefore, are less distinct from each other in their young than in their adult states. The fact of the range of these singular monkeys being so curiously limited as here described, cannot be said to be established until the country lying between the northern shore of the Solimoens and New Granada be well explored, but there can be no doubt of the separation of the two forms in the Delta lands of the Japura, and this is a most instructive fact in the geographical distribution of animals.

The Parauaci Monkey.—Another Ega monkey, nearly related to the Uakaris, is the Parauacti (Pithecia hirsuta), a timid inoffensive creature, with a long bear-like coat of harsh speckled-grey hair. The long fur hangs over the head, half concealing the pleasing diminutive face, and clothes also the tail to the tip, which member is well developed, being eighteen inches in length, or longer than the body. The Parauacti is found on the ‘terra firma” lands of the north shore of the Solimoens, from Tunantins to Peru. It exists also on the south side of the river, namely, on the banks of the Teffé, but there under a changed form, which differs from its type in colours about as much as the red differs from the white Uakari. This form has been described by Dr. Gray as a distinct species under the name of Pithecia albicans. The Parauacti is also a very delicate animal, rarely living many weeks in captivity; but any one who succeeds in keeping it alive for a month or two, gains by it a most affectionate pet. One of the specimens of Pithecia albicans. now in the British Museum was when living the property of a young Frenchman, a neighbour of mine at Ega. It became so tame in the course of a few weeks, that it followed him about the street like a dog. My friend was a tailor, and the little pet used to spend the greater part of the day seated on his shoulder, whilst he was at work on his board. It showed, nevertheless, great dislike to strangers, and was not on good terms with any other member of my friend’s household than himself. 1 saw no monkey that showed so strong a personal attachment as this gentle, timid, silent little creature. The eager and passionate Cebi seem to take the lead of all the South American monkeys in intelligence and docility, and the Coaité has perhaps the most gentle and impressible

disposition; but the Parauacut, although a dull, cheerless animal, excels all in this quality of capability of attachment to individuals of our own species. It is not wanting, however, in intelligence as well as moral goodness, proof of which was furnished one day by an act of our little pet. My neighbour had quitted his house in the morning without taking Parauacti with him, and the little creature having missed his friend, and concluded, as it seemed, that he would be sure to come to me, both being in the habit of paying me a daily visit together, came straight to my dwelling, taking a short cut over gardens, trees, and thickets, instead of going the roundabout way of the street. It had never done this before, and we knew the route it had taken only from a neighbour having watched its movements. On arriving at my house and not finding its master, it climbed to the top of my table, and sat with an air of quiet resignation, waiting for him. Shortly afterwards, my friend entered, and the gladdened pet then jumped to its usual perch on his shoulder. Owlfaced Night Apes.—A third interesting genus of monkeys, found near Ega, are the Nyctipitheci, or night Apes, called Ei-a by the Indians. Of these I found two species, closely related to each other, but nevertheless quite distinct, as both inhabit the same forest, namely, those of the higher and drier lands, without mingling with each other or intercrossing. ‘They sleep all day long in hollow trees, and come forth to prey on insects and eat fruits only in the night. They are of small size, the body being about a foot long, and the tail fourteen inches, and are thickly clothed with soft grey and brown fur, similar in substance to that of the rabbit. The physiognomy reminds one of the owl, or tiger-cat; the face is round and encircled by a ruff of whitish fur; the muzzle is not at all prominent; the mouth and chin are small; the ears are very short, scarcely appearing above the hair of the head; and the eyes are large and yellowish in colour, imparting the staring expression of nocturnal animals of prey. The forehead is whitish, and decorated with three black stripes, which in one of the species (Nyctipithecus trivirgatus) continue to the crown, and in the other (N. felinus) meet on the top of the forehead. N. trivirgatus was first described by Humboldt, who discovered it on the banks of the Cassiquiare, near the head waters of the Rio Negro. One cannot help being struck by this curious modification of the American type of monkeys, for the owl-faced night apes have evidently sprung from the same stock as the rest of the Cebidz, as they do not differ much in all essential points from the Whaidpu-sais (Callithrix), and the Sai-miris (Chrysothrix). They have nails of the ordinary forms to all their fingers, and semi-opposable thumbs; but the molar teeth (contrary to what is usual in the Cebide) are studded with sharp points, showing that their natural food is principally insects.

I kept a pet animal of the N. trivirgatus for many months, a young one having been given to me by an Indian compadre, as a present from my newly-baptised godson. ‘These monkeys, although sleeping by day, are aroused by the least noise; so that when a person passes by a tree in which a number of them are concealed, he is startled by the sudden apparition of a group of little striped faces crowding a hole in the trunk. 22

It was in this way that my compadre discovered the colony from which the one given to me was taken. I was obliged to keep my pet chained up; it therefore never became thoroughly familiar. I once saw, however, an individual of the other species (N. felinus) which was most amusingly tame. It was as lively and nimble as the Cebi, but not so mischievous, and far more confiding in its disposition, delighting to be caressed by all persons who came into the house. But its owner, the Municipal Judge of Ega, Dr. Carlos Mariana, had treated it for many weeks with the greatest kindness, allowing it to sleep with him at night in his hammock, and to nestle in his bosom half the day as he lay reading. It was a great favourite with every one, from the cleanliness of its habits and the prettiness of its features and ways. My own pet was kept in a box, in which was placed a broad-mouthed glass jar; into this it would dive, head-foremost, when any one entered the room, turning round inside, and thrusting forth its inquisitive face an instant afterwards to stare at the intruder. It was very active at night, venting at frequent intervals a hoarse cry, like the suppressed barking of a dog, and scampering about the room, to the length of its tether, after cockroaches and spiders. In climbing between the box and the wall, it straddled the space, resting its hands on the palms and tips of the outstretched fingers, with the knuckles bent at an acute angle, and thus mounted to the top with the greatest facility. Although seeming to prefer insects, it ate all kinds of fruit, but would not touch raw or cooked meat, and was very seldom thirsty. I was told by persons who had kept these monkeys loose about the house, that they cleared the chambers of bats as well as insect vermin. When approached gently, my Ei-a allowed itself to be caressed; but when handled roughly, it always took alarm, biting severely, striking out its little hands, and making a hissing noise like a cat. As already related, my pet was killed by a jealous Caiardra monkey, which was kept in the house at the same time.

I have mentioned the near relationship of the night apes to the Sai-miris (Chrysothrix), which are amongst the commonest of the ordinary monkeys of the American forests. _This near relationship is the more necessary to be borne in mind, as some zoologists have drawn a comparison between the Nyctipitheci and the Microcebi, Nycticebi, and Loris, nocturnal apes of the Lemur family inhabiting Ceylon and Java, and it might be erroneously inferred that our American Ei-ds were related more closely to these Old World forms than they are to the rest of the New World monkeys. The Nycticebus of Java has also large nocturnal eyes, short ears, and a physiognomy similar to that of our Nyctipitheci; resemblances which might seem to be strong proofs of blood-relationship, but these points are fallacious guides in ascertaining the genealogy of these animals; they are simply vesemblances of analogy, and merely show that a few species belonging to utterly dissimilar families have been made similar by being adapted to similar modes of life. The Loris and their relatives of Tropical Asia have six incisor teeth to the lower jaws, and belong, in all other essential points of structure, to the Lemur family, which has not a single representative in the New World. The Ei-ds have teeth of the same number, and growing in nearly the same position, as their near relatives the Sai-miris. I

Page 105 of 120