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Show 260 PROF. HUXLEY ON THE CRANIAL AND [Apr. 6, H 3. ifsNaCWizc. yjsMailSize. A, lower, and B, upper cheek-teeth of Otocyon lalandii; the last molar in the upper jaw is absent; C, the lower sectorial tooth of Otocyon from the inner side, of twice the natural size; D, the corresponding tooth of C. zerda, and E, of C. lupus, reduced to the same absolute length and also viewed from the inner side; a.e. anterior external cusp; a.i. anterior internal cusp; a b. cusp-line. The tooth of the Fennec is obviously intermediate in character between that of Otocyon and that of the Wolf. The comparison of these figures with figs. 6 and 7 will give a very good conception of the extent and the nature of the modifications of the cheek-teeth in the Canidae. the principal inner cusp. In both points this tooth approaches the upper sectorial of Nasua. The crowns of the molars are broader than they are long; but the difference is less than in most Canidae. Their four cusps, with the cingulum on the inner side, are very distinct; and the second upper molar is much larger in proportion to the first than in other Canidae. In the mandible, the third praeniolar has a sharp cusp at the anterior end of its base; the first molar has the inner cusps higher than the outer ones; and the anterior paired cusps are set in a nearly transverse line, the inner hiding the outer when the tooth is viewed from within (fig. 13, C). In both these respects the crown of this tooth |