=The Siluridæ.=—This group has the skin naked or imperfectly mailed, the barbels on the head well developed, the dorsal short, inserted forward, the adipose fin without spine, and the lower pharyngeals separate. All the marine catfishes and most of the fresh-water species belong to this group, and its members, some 700 species, abound in all parts of the world where catfishes are known—"a bloodthirsty and bullying race of rangers inhabiting the river bottoms with ever a lance at rest and ready to do battle with their nearest neighbor." =The Sea Catfish.=—In the tropical seas are numerous species of catfishes belonging to _Tachysurus_, _Arius_, _Galeichthys_, _Felichthys_, and other related genera. These are sleek, silvery fishes covered with smooth skin, the head usually with a coat of mail, pierced by a central fontanelle. Some of them reach a considerable size, swarming in sandy bays. None are valued as food, being always tough and coarsely flavored. Sea birds, as the pelican, which devour these catfishes are often destroyed by the sudden erection of the pectoral spines. None of these are found in Europe or in Japan. Of the very many American species the gaff-topsail catfish (_Felichthys felis_), noted for its very high spines, extends farthest north and is one of the very largest species. This genus has two barbels at the chin. Most others have four. The commonest sea catfish of the Carolina coast is _Galeichthys milberti_. In _Tachysurus_ the teeth on the palate are rounded, in most of the others they are in villiform bands. [Illustration: FIG. 141.—Gaff-topsail Cat, _Felichthys felis_ (L.). Wood's Hole. ] [Illustration: FIG. 142.—Sea Catfish, _Galeichthys milberti_ (Cuv. & Val.). Pensacola. ] In most or all of the sea catfish the eggs, as large as small peas, are taken into the mouth of the male and there cared for until hatched. =The Channel Cats.=—In all the rivers of North America east of the Rocky Mountains are found catfishes in great variety. The channel cats, _Ictalurus_, known most readily by the forked tails, are the largest in size and most valued as food. The technical character of the genus is the backward continuation of the supraoccipital, forming a bony bridge to the base of the dorsal. The great blue cat, _Ictalurus furcatus_, abounds throughout the large rivers of the Southern States and reaches a weight of 150 pounds or more. It is an excellent food and its firm flesh is readily cut into steaks. In the Great Lakes and northward is a very similar species, also of large size, which has been called _Ictalurus lacustris_. Another similar species is the willow cat, _Ictalurus anguilla_. The white channel-cat, _Ictalurus punctatus_, reaches a much smaller size and abounds on the ripples in clear swift streams of the Southwest, such as the Cumberland, the Alabama, and the Gasconade. It is a very delicate food-fish, with tender white flesh of excellent flavor. [Illustration: