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Show 872 MR. OLDPIELD THOMAS ON A NEW [Dec. 17, purposes of this paper, which deals mainly with generic characters, the two have been treated as one. There are, it is true, certain slight differences between Mr. Tomes's description of the teeth of C. fuliginosus and those of the type of C. obscurus, but whether these differences are due to age or specific distinction cannot be made out without direct comparison. GENOLESTES. General appearance not unlike that of a Eat or small Opossum. External characters very much as in the Dasyurid genus Phascologale. Head elongate. Nose naked, both in front and on the top of the muzzle. Ears short, squarish, their inner surfaces provided with several (three in C. obscurus) tragoid projections. Fore feet with five toes, of which the outer one, as well as the pollex, has a distinct nail, while the middle three digits have each a weU-developed curved claw. The third digit is the longest, the second and fourth subequal, about 1 m m . shorter; fifth reaching to the end of the first phalanx of the fourth, first to the middle of the same phalanx of the second. Palms naked, with one elongated carpal pad, three ordinary digital, and one poUical pad. Hind foot of normal shape, not syndactylous, and not modified into a hand as in the Opossums. Hallux short, clawless, not properly opposable *", its development very much as in Phascologale, wallacei2. Other digits subequal, the fourth slightly the longest; all provided with claws. Soles naked, with 6 pads, situated very much as is shown in the figure of Phascologale wallacei just referred to ; but all rather more elongated and not transversely striated. Tail long, slender, rat-like; so thinly haired as to appear naked, its terminal inch below wholly naked ; it is therefore presumably prehensile. " A small and rudimentary pouch present " (Tomes). Skull in its general proportions something like that of a Perameles, although thinner and more delicately built, with a similarly elongated muzzle, smooth and rounded brain-case, and obsolete supraorbital and cranial crest and ridges; the zygomata are, however, so much more boldly expanded as somewhat to spoil the resemblance, which in any case does not apply to details. Nasals long, thin, anterior two-thirds narrow, almost parallel-sided, but a little tapering forwards, their posterior third well expanded, somewhat as in ordinary Didelphys, but not expanded enough to meet the upper edge of the maxillary bone. As a result, an anteorbital vacuity is left on each side in the position of, and formed in exactly the same way as that of, so many Euminants. Apart from the latter group, this vacuity is perfectly unique among Mammals, and therefore is well worthy of special note. 1 Mr. Tomes says " feet furnished with an opposable thumb," but the opposition, at least in C. obscurus, is by no means comparable with that of Didelphys. In the plate neither pollex nor hallux is shown as opposable, and both they and the fifth digit of the hand are ornamented with long claws, about the presence of which I venture to be somewhat sceptical. 2 Figured ' Oat. Marsupials,'pi. xxiii. fig. 3. |