. On the anatomy of vertebrates [electronic resource] . Inferior pharyngeal bone and teeth (Labrus). v. upper pharyngeal bone of the Parrot-fish (Scarus, fig. 255).A thin lamella, slightly curved like a finger-nail, is the singularform of tooth in an extinct genus of fishes, thence calledPetalodus. Sometimes the incisive form of tooth is notchedin the middle of the cutting edge, as in Sargus the edge of the crown is trilobate {Aplodactglus,fig. 256). Sometimes it is made quinquelobate by a double 1 v. pi. 45, fig. 1. B B 2 372 ANATOMY OF Superi notch on eac
. On the anatomy of vertebrates [electronic resource] . Inferior pharyngeal bone and teeth (Labrus). v. upper pharyngeal bone of the Parrot-fish (Scarus, fig. 255).A thin lamella, slightly curved like a finger-nail, is the singularform of tooth in an extinct genus of fishes, thence calledPetalodus. Sometimes the incisive form of tooth is notchedin the middle of the cutting edge, as in Sargus the edge of the crown is trilobate {Aplodactglus,fig. 256). Sometimes it is made quinquelobate by a double 1 v. pi. 45, fig. 1. B B 2 372 ANATOMY OF Superi notch on each side of the large middle lobe (Hoops). In theformidable Sea-pike (Sphyrcena Barracuda) the crown of eachtooth, large and small, is produced into a compressed and sharp255 point, and resembles a lancet. Sometimes the edges of such lancet-shaped teeth arefinely serrated, as in Priodon, and the greatSharks of the genus Carcharias, the fossilteeth of which indicate a species () sixty or seventy feet in length. The lancetted form is exchanged for thestronger spear-shaped tooth in the Sharksof the genus Lamna, fig. 260; and in theallied great extinct Otodus, as in the smallPorbeagle, similarly shaped, but stronger,piercing and cutting teeth were complicatedby one or more accessory com pressed cusps oneach side of their base, like the Malay crease. With respect to situation, the teeth, inSharks and Rays, are limited to the bones(maxillary and mandibular), which form theanterior aperture of the mouth: in theCarp and other Cyprinoids the teeth are confined t
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