Part 57

II. GEOFFROY'S SPIDER-MONKEY, ATELES GEOFFROYI.

Ateles geoffroyi, Kuhl, Beitr. Zool., p. 26 (1820); Schl., Mus. Pays Bas, vii., p. 181 (1876); Alston, in Godman and Salvin, Biol. Centr. Amer. Mamm., p. 8 (1879).

Ateles melanochir, Desmar., Mamm., p. 76 (1820); Gray, Cat. Monkeys Brit. Mus., p. 43 (1870); Sclater, P. Z. S., 1871, p. 226, pl. xv., 1875, p. 419, pls. xlviii. and xlix.

Eriodes frontatus, Gray, Ann. Nat. Hist., x., p. 256 (1842); id. Voy. H.M.S. "Sulphur," Zool., p. 9, pl. i.; Scl., P. Z. S., 1882, p. 186; Von Frantzius, Arch. f. Naturg., xxxv., 1869, pp. 257, 258.

Sapajou geoffroyi, Slack, Pr. Ac. Sc. Philad., 1862, p. 511 (= female).

Ateles variegatus (nec Wagn.), Von Frantzius, Arch. f. Naturg., xxxv., 1869, p. 257.

Ateles hybridus, A. ornatus et A. albifrons, Gray, Cat. Monkeys Brit. Mus., pp. 43 and 44 (1870).

CHARACTERS.--Body light greyish-drab all over; hands, elbows, feet, knees, and the upper side of the extremity of the tail, black; face black, with the exception of the lips and a ring round the eyes, broad above and narrow below, flesh-coloured. Hair of forehead reflexed, meeting that of the crown above the eyes, forming a triangular patch of erect black hairs. Top of the head and upper part of the tail buff. Length of body, 17 inches; of tail, 21 inches. Thumb entirely wanting.

This species is remarkably variable. The description given above belongs to the form described as A. melanochir by {234}Desmarest from the same specimen in Paris, which Kuhl described under the name of A. geoffroyi. Every gradation is to be met with between this and the form described by Dr. Gray as A. ornatus, in which the face is entirely black, the whiskers pale reddish-yellow, the patch of erect black hair on the forehead yellowish at its base; the top of the head, sides, lower back, rump, upper part of the arms, outer, inner and posterior portion of the thighs and legs, and under side of the base of the tail, brownish-red; nape, shoulders and remainder of the tail reddish-brown, washed with black; lower part of arms, fore-arms, hands, feet, and anterior aspect of thighs and legs, black.

In some specimens the grey, or reddish-black colour, merges on the under surface, into yellowish-cream, or rufous, and the black wash is more or less distributed.

Mr. Alston, in speaking of this species, remarks that the best character by which the darker (A. ornatus) forms may be distinguished from our next species (A. rufiventris) is the want of a distinct line of demarcation between the colours of the upper and lower parts, the tint of the flanks, whatever it may be, passing almost insensibly into that of the breast and belly in all the varieties.

DISTRIBUTION.--The variation in colour described above is not due to local causes, every variety occurring between the lightest and darkest, in all the regions which this species is known to inhabit. The localities from which it has been recorded are on both the Atlantic and Pacific coasts of Nicaragua; Costa Rica, where it occurs in large numbers from the coast forests up to nearly 7,000 feet on the mountains; Panama, and the U.S. of Colombia.

HABITS.--Geoffroy's Spider-Monkey is gregarious and arboreal, {235}frequenting the highest trees of the forest, both in the low country and at high elevations, and living on fruits and insects, but chiefly on the former. Mr. Belt relates that on the banks of the Antigua he saw a valuable tree, the "Nispera" (Achras sapota), growing on the dryer ridges. "It bears a round fruit about the size of an apple, hard and heavy when green, and at this time it is much frequented by the large yellowish-brown Spider-Monkey (Ateles), which roams over the tops of the trees in bands of from ten to twenty. Sometimes they lay quite quiet until I was passing underneath, when, shaking a branch of the Nispera tree, they would send down a shower of the hard round fruit; but fortunately I was never struck by them. As soon as I looked up they would commence yelping and barking and putting on the most threatening gestures, breaking off pieces of branches and letting them fall, and shaking off more fruit, but never throwing anything, simply letting it fall. Often when on lower trees, they would hang from the branches, two or three together, holding on to each other and to the branch with their fore-feet and long tail, whilst their hind-feet hung down, all the time making threatening gestures and cries. Sometimes a female would be seen carrying a young one on its back, to which it clung with legs and tail, the mother making its way along the branches, and leaping from tree to tree, apparently but little encumbered by its baby. A large black and white Eagle is said to prey upon them, but I never saw one, although I was constantly falling in with troops of the Monkeys. Don Francisco Velasquez, one of our officers, told me that one day he heard a Monkey crying out in the forest for more than two hours, and at last, going to see what was {236}the matter, he saw a Monkey on a branch and an Eagle beside it trying to frighten it to turn its back, when it would have seized it. The Monkey, however, kept its face to its foe.... Velasquez fired at the Eagle, and frightened it away. I think it likely, from what I have seen of the habits of this Monkey, that they defend themselves from the Eagle's attack by keeping two or three together, thus assisting each other, and that it is only when the bird finds one separated from its companions that it dares to attack it."

Mr. Osbert Salvin met with several of these Monkeys near the town of San Juan del Sur, in Nicaragua. He was walking up the course of a half-dry stream when he came upon a troop of Monkeys which had come to a pool to drink, and were climbing about the low trees on the bank of the watercourse. Most of the troop consisted of Cebus hypoleucus, but with them were several Ateles of the present species, of one of which Mr. Salvin wrote a description as it sat jabbering at him and throwing down sticks from a branch above his head. Mr. Salvin also told Mr. Alston that it was not unusual to see Monkeys kept in confinement in the court-yards of the Spanish houses in Guatemala. Amongst them were occasionally to be seen specimens of Geoffroy's Spider-Monkey; but he always found that they had been brought from Nicaragua or Costa Rica, the species not extending into Guatemala.

III. THE RED-BELLIED SPIDER-MONKEY. ATELES RUFIVENTRIS.

Ateles vellerosus (?) (nec Gray), Scl., P. Z. S., 1871, p. 478.

Ateles rufiventris, Scl., P. Z. S., 1872, p. 688, pl. lvii.; Schlegel, Mus. Pays Bas, vii., p. 182 (1876).

CHARACTERS.--Fur rough, upstanding less on the tail than on {237}the body, that on the forehead erect and directed backwards, that on the top of the head long, projecting forward. Face and muzzle, except a black line from the side of the nose and inner corners of the eyes to the cheeks, flesh-coloured. General colour uniform black, but the whole under surface deep bright rufous, this colour extending but slightly on to the inner surface of the limbs. Thumbs entirely wanting.

Differs from A. geoffroyi by its flesh-coloured face and by the two colours of the upper and under sides being clearly defined. Length of body, 12 inches; of tail, 15½ inches.

DISTRIBUTION.--This species was first discovered on the Atrato river, in Northern Colombia, and has since been found in Panama.

HABITS.--The Red-bellied Spider-Monkey is very rare, only one or two specimens having yet been obtained. Nothing is, therefore, known of its habits.

IV. THE RED-FACED SPIDER-MONKEY. ATELES PANISCUS.

Simia paniscus, Linn., Syst. Nat., i., p. 27 (1766).

Ateles pentadactylus, Geoff., Ann. Mus., vii., p. 269 (1806); Schl., Mus. Pays Bas, vii., p. 172 (1876, in part).

Ateles paniscus, Geoff., Ann. Mus., vii., p. 270 (1806); Gray, Cat. Monkeys Brit. Mus., p. 42 (1870); Schl., Mus. Pays Bas, vii., p. 169 (1876, part.).

Le coaita, F. Cuv. et Geoffr., Nat. Hist. Mamm., liv., v. (Avril, 1819).

Sapajou paniscus, Slack, Proc. Acad. Nat. Sci. Philad., p. 509 (1862).

CHARACTERS.--Very similar to A. ater in its coarse and entirely black fur, but differing in the naked and flesh-coloured {238}face. Hairs of forehead long and projecting anteriorly; tail one-quarter longer than the body; hands generally entirely lacking the thumbs, though sometimes a rudimentary thumb is present, and that occasionally on one hand only. Naked portion of tail covered with sensory papillæ, rendering it more sensitive, so it is said, than the hand. Length of body, 24 inches; tail, 30 inches. The skull in some specimens of the thumbed variety is compressed laterally, and shows a sagittal crest along the top.