Table of Contents
Although the ocean sunfishes are allied anatomically to the puffers and porcupine fishes, with which they agree in the very small gill openings and in the fusion of the teeth into a sort of bony beak, they bear no resemblance whatever to them in general appearance, for they appear to consist of nothing but a "huge head to which the fins are attached," as Jordan and Evermann aptly express it. They have no spiny dorsal fin; the soft dorsal and anal fins are short and very high, and they have no caudal peduncle. The caudal fin, so short that it is apparently nothing more than a flap of skin, extends all around the rear outline of the trunk. Corresponding to their extraordinary conformation the sunfishes, have only 16 or 17 vertebrae.
All known members of the family are oceanic in nature, and they are widely distributed in warm seas. One (Mola mola, p. 529) is a rather frequent [page 529] visitor to our Gulf from the south; and a second (Masturus lanceolatus) has, perhaps, a claim to mention here, on the strength of one very young sunfish that was taken in Massachusetts Bay many years ago (p. 532).
|KEY TO GULF OF MAINE SUNFISHES|
|1.||There is no evident caudal fin||—||Sunfish, p. 529|
|2.||There is an evident caudal fin, extending horizontally across the posterior edge of the trunk, with a triangular lobelike extension a little above the midlevel of the body||—||Sharp-tailed sunfish, p. 531|
 Bull. 47, U. S. Nat. Mus, Pt. 2, 1898, p. 1752.