Vertebral column more or less completely ossified, heterocercal. Body covered with cycloid scales. Branchiostegals present.
First Family—Caturidæ.
Notochord persistent, with partially ossified vertebræ; homocercal; fins with fulcra. Teeth in a single series, small, pointed.
Extinct. Caturus from the Oolite to the Chalk.
Fig. 148.—Caturus furcatus (Solenhofen).
Second Family—Leptolepidæ.
Scales cycloid. Vertebræ ossified; homocercal; fins without fulcra; dorsal short. Teeth minute, in bands, with canines in front.
Extinct, and leading to the living representative of this suborder. Thrissops with the dorsal fin placed far backwards, and opposite to the long anal. Leptolepis with the dorsal fin opposite to the ventrals, from the Lias and Oolite. These fishes, as far as the preserved parts are concerned, cannot be distinguished from Teleosteous fishes, to which they are referred by some Palæontologists.
