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Show 1885.] DR. ST. G. MIVART ON THE ARCTOIDEA. 385 postorbital processes, though the latter may be very slightly marked or strongly so. The skull is extremely pinched in behind the orbits. There is a large sagittal and very large lambdoidal ridge. The skull is extremely broadened out behind, but the muzzle is very short. The postglenoid process is much developed, and tends to hold the mandible as in the Badger. The basioccipital is very thin, and defect of ossification may exist in it and in the exoccipitals. The rhinencephalic fossa is also shallower than heretofore1. The crista galli is large. The turbinals are very large and complex. The infraorbital foramen is enormously large. The angle of the mandible is much as in Meles but rather strongly everted, the ascending ramus being very concave externally. Molar formula=-P. f, M . \. The middle incisor of each ramus of the mandible is placed behind the other two. The upper sectorial and molar are much like those of Helictis2, save that the antero-internal cusp of the former is smaller. The lower molar teeth are also much like those of Helictis, except that the second true molar is a little larger relatively. In the upper jaw the first premolar is minute; the second and third, each simple and conical, but greatly increasing in size, and with an external cingulum; the fourth has three external cusps, of which the median one greatly predominates, and an external cingulum. There is a very large internal cingulum embracing the postero-internal part of the tooth, which is two thirds the length of the external part. The upper molar has two external cusps and a small external cingulum, with one internal principal cusp, and a large internal cingulum, which may develop another internal cusp. In the lower jaw all the giinders have an external cingulum. The three premolars are pretty simple and conical, successively increasing in size backwards. The sectorial has two external and one internal principal cusps, with a large talon developing small accessory cusps. The second molar is small and rounded. The tongue has the papillae which clothe it pretty uniform in size, except that the flattened papillae are elongated and rather conspicuous. There are five circumvallate papillae forming a V, open forwards. Of the salivary glands the parotid is thin, and the submaxillary is larger than the parotid ; it is, indeed, large and bilobed. The larynx has the thyroid cartilage rather sharply notched, medianly below. The lungs have the form usual in the Carnivora. The diaphragmatic aspect of the liver is very like that presented by Nasua, as also is that of its abdominal aspect, save that the Spigelian lobe is subdivided and the caudate large, and especially longer. The kidney differs greatly from that of all Arctoids yet described, and from that of all non-Arctoid Carnivores. Instead of being single, with one mamilla, it is lobulated, each of the many lobes being a little kidney in itself, with one mamilla. 1 Other Pinniped characters. 2 See antea, p. 374. |