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Show 396 DR. ST. G. MIVART ON THE ARCTOIDEA. [Apr. 21, Comparison of the ARCTOIDEA with the other FISSIPEDAL CARNIVORA. It would be superfluous to here again refer to the cranial or genital characters which differentiate the three suborders of the Carnivora. As to the dentition, the Arctoids alone of the existing forms present us in one genus with but four lower incisors, a condition also characteristic of the extinct iEluroid Fusmilus. They alone afford examples of upper true molars, which are broad and formed for crushing, and only in them do we find a fourth lower premolar, which is broad posteriorly. The dentition may nevertheless be extremely sectorial or more formed for crushing than in any other Carnivore ; but the teeth are never so rudimentary as in Proteles. Only in them (Grisonia) do we find as many as sixteen dorsal vertebrae. They possess a brain which has a definite character in the almost constant presence of a dorsal patch limited incompletely by crucial and precrucial grooves, which have been called the " Ursine lozenge." While perineal glands are absent, we occasionally find a new glandular structure-a subcaudal gland, as in Meles and Tax-idea. Less exclusively terrestrial than the Cynoids, they are never so arboreal as are some of the iEluroids ; but they present us with more fossorial genera, and with others perhaps more definitely modified for aquatic life than is the iEluroid Cynogale. As to the coloration of this group, the Arctoids have frequently longitudinal markings, often of black and white, while they never show the spots or transverse bands which are found in many iEluroids. All the Arctoidea are pentadactyle. There is a great difference between the Arctoidea and the other Carnivora as regards the vertical median nose-groove. Very rarely absent in the iEluroids, it is, as we have seen, absent in a good many genera of Arctoids, and sometimes, as in Ursus, present or absent in different species of the same genus. Only in the Arctoids, but almost always in them, the crucial and precrucial sulci define an " Ursine lozenge " on the surface of the cerebrum. Distribution of the ARCTOIDEA. This suborder extends all over the world except Australia, New Zealand, N e w Guinea and adjacent islands, Polynesia, Madagascar, the Antilles, and the Antarctic region. The Procyonida are exclusively New-World forms, the Ailurida are exclusively Asiatic. The Mustelida and Ursida are cosmopolitan within the range of the suborder. The majority of the species and genera belong north of the equator. No genera except U?-sus, Gulo, Mustela, Putorius, and Lutra are common to the Old and New Worlds, and no species are common to them save Gulo luscus, Putorius vulgaris, Putorius erminea, and Ursus maritimus. The genera common to Asia and Africa are Mustela, Putorius, Lutra, Ursus, Mellivora, and Aonyx. The genera peculiar to Africa are Lctonyx and Pcecilogale. The genera peculiar to Asia are Ailurus, Ailuropus, Helictis, Arctonyx, |