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Show 1885.] DR. ST. G. MIVART ON THE ARCTOIDEA. 377 below it is much flattened and everted. The angle is, however, more conspicuous than in Arctonyx or Mydaus. Molar formula=P. |, M . \. The fourth upper premolar is formed like that of the Civet. The first upper true molar is very short but wide, more like that of Llyana than is the same tooth in any Arctoid yet here noticed. It is, however, relatively wider within than without inwards. There are two minute external tubercles and a yet smaller internal one, within which is a large internal cingulum. The three inferior premolars are much as in Meles. The first lower true molar is very sectorial, and not quite like any tooth as yet here described. It is a good deal like that of the Civet, with the talon reduced, or like the front half of the same tooth in Meles, with only a very small talon instead of the large one of the Badger. The most anterior cusp is narrower than the one behind it, and their adjacent margins form together an acute angle. The second true lower molar is a small rounded tooth. The liver is very like that of Nasua, but the part of the right central lobe which is on the left of the gall-bladder is large. The brain *• is very complicated in its dorsal convolutions. The Sylvian fissure is long and oblique and the anterior limb of the Sylvian gyrus is very decidedly the narrower. There is a small Ursine lozenge. The crucial and calloso-marginal sulci do not join, a bridging convolution connecting the hippocampal and sagittal gyri behind the crucial sulcus. Grisonia 2.-The Grison has a tail about half the length of its slender body. The nose is destitute of any median groove and the muzzle is rather acute. The eyes are short, broad, and rounded ; the legs are short. The soles are naked, and locomotion is semiplanti-grade. It inhabits Tropical and South America. There are 16 dorsal, 5 lumbar, 3 sacral, and 21 cervical vertebrae. It has the relatively shortest Arctoid radius except Lutra. Compared with the length of the head it has the broadest palate of any Arctoid. The only cranial differences from Galictis I observed were that the foramen glenoideum is very small, instead of large, and that the meatus auditorius externus is both long and very wide. The first cusp of the first lower molar is wide, and quite as wide as the second, and their adjacent edges form an obtuse angle. The liver is like that of Galictis, but the left central lobe is smaller, and the right central lobe is uniform in its diaphragmatic aspect. 1 See I. c. pp. 15 & 16, figs. 4 & 5. 2 See Schreber, Saug. p. 447, pi. 124; Thunberg, Mem. Acad. St. Petersb. vi. p. 401, pi. 13; Traill, Mem. Wern. Soc. iii. p. 437, pi. 19; Desmarest, Mam. p. 175; Molina, Chile, iv. p. 258; Shaw, Gen. Zool. i. p. 433; Bell, Trans. Zool Soc. ii. p. 204, pi. 37; Buffon, H. N. Supp. iii. p. 170, pi. 25; Martin, P. Z. S. 1833, p. 140; Gray, P. Z. S. 1865, p. 122, Cat. Carniv. B. Mus. p. 99; De Blainville, Osteog. Mustela; Waterhouse, Zool. of ' Beagle,' i. p. 21 ; Wagner, Supp. ii. p. 215 ; P. Gervais, Mamm. ii. p. 110; Azara, Ess. i. p. 190. |