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Show 1882.] PROF. ST.-GEORGE MIVART ON THE ALUROIDEA. 199 in both species, there is a transverse band of isolated follicles at the bottom of the anal pouch. The penis is long and pendulous, and entirely devoid of any bone. There are fifteen dorsal vertebrae. The cranium of Hyana differs from every Viverrine cranium by its enormous sagittal and lambdoidal ridges, and strong and greatly arched zygomata. The general type of its construction is Viverrine, though there is no alisphenoid canal or septum between the anterior and posterior portions of the auditory bulla. As to the first point, we have seen that the canal is generally wanting in Viverricula, and constantly so in the Galidictina and Eupleres. As to the auditory bulla, it is interesting to note that the aperture between the chambers is enlarged in the Herpestina (which by their circumanal pouch resemble the Hyanida) ; and though there is no septum, yet I have detected in both species of Hyana, inside the auditory bulla, two osseous ridges or laminae, which if further developed would divide off a small anterior chamber from the much larger and externally more prominent posterior portion. The anterior portion of the margin of the external opening of the auditory meatus (which has no fissure or foramen in its floor) is much more produced than any other part-an exaggeration of a character we have already seen in the Herpestina. There is no pterygoid fossa. The postorbital processes are short and blunt, and widely separated from the malar processes. The skull is not pinched in behind them. The condyloid foramen is concealed. The paroccipital is long and depending. The mastoid is rather prominent. The carotid canal is much more Viverrine than Feline : its posterior opening is always larger, and generally situated much more anteriorly than in the Felida, and more approaching its situation in the Viverrina. There is no carotid foramen in the sphenoid ; but it enters the cranium (beside the hinder end of the sella turcica) through the foramen lacerum, and covered in by the auditory bulla. The palate is much prolonged behind the last molars. The lower border of the mandible is m u c h curved ; the angle is flattened along its inferior border, and is pressed up nearer to the condyle than in Felis or in any other iEluroid I have seen-Nandinia (which also has rather strongly developed cranial ridges) being most like it in this respect, except, of course, Crocuta and Proteles. The teeth of Hyana ' are so well known that I hesitate to re-describe them ; but I feel any utility this paper may possess would be greatly impaired if their resemblances and differences to other iEluroids, and especially to the Cats, were not shortly noted in it. The outer upper incisors are canine-like, and much more preponderant over the inner ones than in the Cats. The canines, on the other hand (both above and below), are relatively shorter, more flattened internally, and without longitudinal grooves either outside or inside. ^-^ is relatively larger than in Felis (though I have observed it to be 1 Figured by De Blainville (Hyenes, pl. vi.) and Cuvier (Dents des Mamm. pl. 25). For osteology, see Cuvier's ' Ossemens Fossiles,' 4th edition (1835), vol. vii. p. 311, and Atlas, vol. ii. pl. 190. |