Distribution.—Arctic, temperate, and tropical seas. Species of Acanthias, Læmargus, and Echinorhinus have occurred on our coasts.

Family 106.—RHINIDÆ (1 Genus, 1 Species.)

"Sharks with depressed flat body and large expanded pectoral fins."

Distribution.—Temperate and tropical seas, from Britain to California and Australia.

Family 107.—PRISTIOPHORIDÆ. (1 Genus, 4 Species.)

"Sharks with produced flat snout, armed with teeth on each edge."

Distribution.—Seas of Japan and Australia.

Sub-order Batoidei. (Rays.)

Family 108.—PRISTIDÆ. (1 Genus, 5 Species.)

"Rays with produced snout and lateral saw-like teeth."