"Diagram of the anterior fin (archipterygium) of Ceratodus." — Galloway

Archipterygium

"Diagram of the anterior fin (archipterygium) of Ceratodus." — Galloway

"Burbot (Lota vu'garis), with jugular ventral fins." — Encyclopedia Britannica, 1893

Burbot

"Burbot (Lota vu'garis), with jugular ventral fins." — Encyclopedia Britannica, 1893

"Dissected fish. a, air bladder; b, urinary bladder; b, urinary bladder; br, brain; c, spinal cord; d and da, dorsal fins; dv, anal fin; e, body of the vertebra; g, gills receiving the blood from the ventral aorta leading out of the heart h; i, intestine; k, kidney; l, liver; m, spines of the vertebra; n, auricle of the heart; ov, ovary; ovd, oviduct; st, stomach; sp, spleen; u, ureter." —Davison, 1906

Dissected Fish

"Dissected fish. a, air bladder; b, urinary bladder; b, urinary bladder; br, brain; c, spinal cord;…

An illustration of a fish fin.

Fish Fin

An illustration of a fish fin.

"Section of <em>Ampioxus</em>, fr, fin ray; ct, connective tissue; nc, notochord, ; snc, supraneural crest"&mdash;Finley, 1917

Section of a lancelet

"Section of Ampioxus, fr, fin ray; ct, connective tissue; nc, notochord, ; snc, supraneural…

"Side view of <em>Amphioxus</em>: fs, fin supports; nc, notochord; ot, oral tentacles."&mdash;Finley, 1917

Side view of lancelet

"Side view of Amphioxus: fs, fin supports; nc, notochord; ot, oral tentacles."—Finley,…

"Mullus barbatus (Red Mullet), with thoracic ventral fins." &mdash; Encyclopedia Britannica, 1893

Red Mullet

"Mullus barbatus (Red Mullet), with thoracic ventral fins." — Encyclopedia Britannica, 1893

A rudder supported on a skeg or projection from the keel, about one third of its surface being forward and two thirds abaft its vertical axis.

Balance Rudder

A rudder supported on a skeg or projection from the keel, about one third of its surface being forward…

"Salmo salar (Salmon), with abdominal ventral fins." &mdash; Encyclopedia Britannica, 1893

Salmon

"Salmo salar (Salmon), with abdominal ventral fins." — Encyclopedia Britannica, 1893

"Saurus undosquamis, a Malacoptorgian with anterior soft dorsal and additional adipose fin." &mdash; Encyclopedia Britannica, 1893

Saurus Undosquamis

"Saurus undosquamis, a Malacoptorgian with anterior soft dorsal and additional adipose fin." —…

"The seal, adapted principally for water. The extremities are larger than in the porpoise and manatee."&mdash;Pettigrew, 1874

The Seal

"The seal, adapted principally for water. The extremities are larger than in the porpoise and manatee."—Pettigrew,…

"Pectoral girdle and fin of a Teleost. br.o., branchial ossicles; c, coracoid; cl., clavicle; f.r., fin rays; p.cl., post clavicle; p.t., post temporal which unites with skull; sc., scapula; s.cl., supra-clavicle." &mdash; Galloway

Teleost

"Pectoral girdle and fin of a Teleost. br.o., branchial ossicles; c, coracoid; cl., clavicle; f.r.,…