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Show 1880.] DENTAL CHARACTERS OF THE CANIDAE. 253 De Blainville long since figured and called attention to this feature m,e m a n d l b l e ln 0. cinereo-argentatus. These peculiarities are closely reproduced in the Thooid series, by the skull of a South-American animal referred to Canis azaree\ which died in the Gardens of the Society, and to which I have alluded above as C azarce (a) (fig. 8 A, p. 251). The sagittal area is wide and lyrate; but the temporal ridges are not so strongly marked as in C. littoralis. There are no strong depressions on the supraorbital processes ; and the glabella is evenly arched, in correspondence with the small but distinct frontal sinuses. The angular process of the mandible is extremely strong, and its margin is thick and tumid. Beneath it there is a well-developed subangular lobe (fig. 9 A, L ). The following table of proportional measurements (basicranial axis = 100) shows how closely C. azaree (a) and C. littoralis represent one another. TABLE V.-Proportional Measurements of the Skull and Teeth of C. azarae (a) and C. velox. C. azarce (a). • C. velox. Total length of bony palate 125 122 breadth of „ 78*9 71 length of 22Li 22*4 22*4 - 17*7 18*1 ^ 11*1 13*3 J> >> >> >> m. 1 TO. 2 27'7 27*2 14*4 15*7 In both, a small accessory cusp is developed on the posterior part of the outer face of the external anterior or principal cusp of the lower sectorial tooth (fig. 9, A and B ). Nevertheless the frontal sinuses and the form of the anterior part of the cerebral cavity at once distinguish C. azarce (a), as a Thooid, from C. littoralis. 7. The transition between C. azarce (a) and the macrodont Thooids is furnished by the skull of an animal from Pernambuco, which died in the Gardens, and came to m e labelled (iC.fulvipes'" (fig. 10, p. 254). The sagittal area is much narrower than in G. azaree (a); and the temporal ridges unite into a short median crest behind. The glabella is convex, and the postorbital constriction small, in correspondence with the considerable development of the frontal sinuses. The angular process of the mandible (fig. 9, C, A ) is deep, strong, and thick, but not tumid as in the foregoing species. The subangular lobe is 1 Mr. Forbes informs m e that this animal possessed a short straight caecum. C. cancrivorus has a similar caecum. In C. procyonoidcs, C.jubatus, and Icticyon venaticus the caecum is longer and larger, but almost straight. In all the other Oanicte (certainly in C. lupus, C. laniger, C. domcsticus. C. aureus, C. anthus, C. antarcticus, C. azarce, in Cyon, Lyceum, Vulpes, and Otocyon) it would appear that the czecurn is large and coiled. (See Garrod, P.Z.S. 1873 and 1878; Murie, P. Z. S. 1873; Flower, P. Z. S. 1880.) |