Table of Contents
The chimaeroids, being cartilaginous fishes, are allied to the sharks, skates and rays, but are separated from them by many important anatomic characters. Most obvious of these externally are that they have no spiracle; that they have only one external gill opening on either side; that their tails are symmetrical; and that their gill filaments are free at the tips like those of bony fishes. The chimaeroids remotely suggest the grenadiers in general body form (p. 243), but are easily separable from them at a glance; first of all by the softness of their bodies and by their naked skins, also by the location of the pelvic fins which are set far back under or behind the tips of the pectorals, and by the large size of the pectoral fins, to list only the most obvious differences. There is no danger of confusing them with any other Gulf of Maine fishes, so curious is their appearance.
They lay eggs that are astonishingly large for the size of the parent fish, and enclosed in brown horny capsules which are elliptical, spindle-shaped or tadpole-shaped in different species. But fertilization is internal.