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Show 512 DR. A. G U N T H E R O N A ZOOLOGICAL [June 23, Lower incisors small, separated in the centre, the inner about the size of the outer, the combined diameters of those of each side 2 millim. Canines proportionally still shorter than in the upper jaw, 3*5 millim. from cingulum to tip behind; their basal ledge broad. Anterior premolar very large, nearly filling up the space between the canine and second premolar, its size in cross section nearly equal to that of the canine. Molars smooth and rounded, as in the upper jaw. Last molar in section about one-third the size of the anterior premolar, and three quarters that of the last upper molar. Dimensions of the type, specimen a, an adult female in spirit:- Head and body 210 millim.; head 61 ; muzzle 22; ear, above crown 26, from notch at base 28 ; forearm 127 ( = 5 0 in.) ; thumb, without claw, 43 ; index finger 90 ; tibia 62 ; calcaneum 21. Skull:-Basal length 52; greatest breadth30 ; supraorbital foramen to tip of nasals 24*5 ; interorbital breadth 6*5 ; intertemporal breadth 5-0; breadth from tip to tip of postorbital processes 191 ; palate, length 32, breadth outside first molar 16*0 ; length of first molar 5*0. It is unfortunate that of this new species the only specimens of any use for description are females, since it might happen that, as is sometimes the case in Pt. nicobaricus, while the females are wholly black, the males have the usual yellow or orange tippet. It is therefore much to be hoped that male specimens will soon be obtained and the point settled. In any case, however, Pt. natalis is a very well-marked species. From Pt. nicobaricus it may be distinguished by its much smaller size and smaller shorter molars, and especially by its much shorter and feebler canines-the latter character, in fact, distinguishing it from all the other allied species except Pt.lombocensis. Pt. pselaphon, another wholly black species of about the same size, a native of Bonin, mav be separated at once by its hairy legs, the hind limbs being closely haired right down to the feet. Pt. gouldi, also generally black, has a forearm 165 millim. long, and has also large teeth and long canines bearing no resemblance to those of the present species. On tbe whole Pt. natalis seems to be most nearly allied to Pt. lombocensis, Dobs.1, as yet only known from Lombock, which also has similarly short canines and is of about the same size. That animal, however, is of a dull light brown colour, with the neck pale yellow. Its teeth, especially the anterior molar, are narrower and lighter than those of Pt. melas; the first lower premolar and the last molars both above and below are much smaller, and the basal ledges to the canines are decidedly narrower than in Pt. natalis. In the skull, again, Pt. lombocensis has a shorter broader muzzle, greater spread of zygomata, broader interorbital space, and larger postorbital processes than the present species. Of course in comparing the colours of these two species the question of sex again arises, as the only known specimens of Pt. lombocensis are both males ; but considering not only the differences in the skull and teeth, but also the fact that even if the male of Pt. natalis have a yellow tippet, it would in all probability have at least its head and body jet-black like 1 Cat. Chir. B. M. p. 34 (1878). |