. The cyclopædia of anatomy and physiology. Anatomy; Physiology; Zoology. 902 TEETH. (herbivorous Cetacea of Cuvier) differ in has been called in question.* I have, how- many organic particulars from the Cetacea ever, discovered in specimens of the Malayan. Dentition of the Dugong (Halicore inclicus). proper*, and in none, perhaps, more strikingly than in having both deciduous and permanent teeth; this succession takes place, at least, with regard to the upper incisors of the Du- g°}lff, fig- 575. These teeth project from the gum in the male sex ; but neither upper nor lower in- cisors are vis
. The cyclopædia of anatomy and physiology. Anatomy; Physiology; Zoology. 902 TEETH. (herbivorous Cetacea of Cuvier) differ in has been called in question.* I have, how- many organic particulars from the Cetacea ever, discovered in specimens of the Malayan. Dentition of the Dugong (Halicore inclicus). proper*, and in none, perhaps, more strikingly than in having both deciduous and permanent teeth; this succession takes place, at least, with regard to the upper incisors of the Du- g°}lff, fig- 575. These teeth project from the gum in the male sex ; but neither upper nor lower in- cisors are visible in the The supe- rior incisors are but two in number, in both sexes ; in the male, they are moderately long, subtriedral, slightly and equally curved, of the same diameter from the base, and deeply excavated to near the apex, which is obliquely bevelled off to a sharp edge, like the scalpriform teeth of the Rodentia. The form and extent of the persistent pulp-cavity of this tooth are shown in the figure of its longitudinal section, in my " Odontography," pi. 93. fig. 4.; it becomes longer and more pointed than in the permanent incisor of the younger male (fig. 575, z). When fully de- veloped, only the extremity of this tusk pro- jects from the jaw, at least seven-eighths of its extent being lodged in the socket, the parietes of which are entire; and the exterior of the great premaxillary bones presents an unbroken surface. In the female Dugong, the growth of the permanent incisive tusks of the upper jaw is arrested before they cut the gum, and they remain through life concealed in the premaxillaries; the tusk is solid, is about an inch shorter and less bent than that of the male ; it is also irregularly cylin- drical, longitudinally indented, and it gradually diminishes to an obtuse rugged point ; the base is suddenly expanded, bent obliquely outwards, and presents a shallow excavation. These were conjectured by Home to be the " milk-tusks ; &qu
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