Callous, indurated.

Callosity, a protuberance.

Calcareous, relating to lime.

Canal, the prolongation of the beak.

Canaliculated, channeled or grooved.

Cardinal, see Teeth.

Carinated, like a boat’s keel.

Cartilage, a flexible fibrous substance by which the valves are united.

Cartilaginous, resembling a ligament.

Chambered, divided by partitions.