| OCR Text |
Show 14 MR. W. II. FLOWER ON THE [Jail. 14, that genus. There are only a few partial septal bands across the floor, as in the Badgers. The anterior inferior extremity of the bulla is pointed, and commonly united to the prolonged hamular process of the pterygoid. The whole of the genera above described are united by Mr. Turner into one family, Ursidee; and that they constitute a natural group, I think no one should doubt, even on grounds independent of their cranial characters. They all agree in having the intestinal canal without a caecum, all other known Carnivora possessing this appendage. Moreover they all agree together, and differ from all other Carnivora, in the structure of the generative organs of the male, parts of considerable value in determining affinities. They all have a large penis, with a very considerable bone, which is usually more or less curved, somewhat compressed, not grooved, dilated posteriorly, and often bifurcated, or rather bilobed, in front. They are all destitute of Cowper's glands. All have the prostate rudimentary, or consisting only of a thickening of the wall of the urethra and forming no distinct prominence. Among all the diversity that has been shown to exist in the characters of tbe base of the cranium, especially in the form of the auditory bulla, the following points of general agreement are to be found :- 1. The cavity of the bulla is simple (as compared with another form to be described presently). That is, although there are frequently trabeculae or partial septa passing mostly transversely across the lower part, and generally connected with the tympanic ring, there is no distinct and definite septum dividing it into a separate outer and inner character. In all cases, on looking into the external auditory meatus (in the dried skull when the membrana tympani is removed) the opposite wall of the bulla can be seen ; or if a probe is passed into the meatus, no obstacle will prevent its touching the inner wall. Whatever the diversity of development of the buna, it always has its greatest prominence near the middle of the inner border, and slopes away from that point, not only externally, but also forwards and backwards. 2. The inferior lip of the external auditory meatus is always considerably prolonged. 3. The paroccipital process is more or less triangular, and directed backwards, outwards, and downwards, standing quite aloof from the bulla. This relation depends chiefly on the want of development of the posterior portion of the bulla; and is absent, or obscure in Mustela alone. 4. The mastoid process is widely separated from the paroccipital and generally very prominent. ' 5. The carotid foramen is always large, and placed usually near the middle, but sometimes more posteriorly, on the inner margin the u co argm of e bulla. It is generally very conspicuous, but sometimes partiallv ncealed by the projecting lip of the basioccipital. 6. The condyloid foramen is distinct and exposed ; and although sometimes partially overlapped posteriorly by a ridge of bone passine |
