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Show 344 DR. ST. G. MIVART ON THE ARCTOIDEA. [Apr. 21, "Subfamily PROCYONINA (confined to America). " No alisphenoid canal. " True molars on each side ^. Procyon. Cercoleptes. Nasua. Bassaris. " Subfamily MUSTELINA (of general geographical distribution). " N o alisphenoid canal. "True molars on each side 3. Arctonyx. Grisonia. Meles. Galera. Taxidea. Fison. Mydaus. Mus tela. Mephitis. Martes. Gulo. Helictis. Lutra." Mellivora. The distinctions and observations of Mr. Turner have been further developed and perfected by Professor Flower in his elaborate paper on the Classification of the Carnivora1, wherein the principal cranial characters of nearly all the Arctoid genera are described, with figures of the skulls of Ursus, Putorius, Procyon, and Bassaris (figs. 1, 2, 3, 3a, and 4), and their points of agreement are summed up as follows2:-"They all agree in having the intestinal canal without a caecum, all other known Carnivora3 possessing this appendage. Moreover they all agree together, and differ from all other Carnivora, in the structure of the generative organs of the male, facts 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 in the characters of the 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 (compared with Felis). 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 chamber. In all cases, on looking into the external auditory meatus (in the dried skull when the membrana tympani is removed) the opposite wall of 1 P. Z. S. 1869, p. 4. 2 L. c. p. 14. 3 Subsequently Prof. Flower discovered that the caecum is absent mNandinia. It may also be entirely absent in Arctictis. |