_Pomacentrus_, locally known as pescado azul, abound in the West Indies and on the west coast of Mexico. _Pomacentrus fuscus_ is the commonest West Indian species, and _Pomacentrus rectifrenum_ the most abundant on the west coast of Mexico, the young, of an exquisite sky-blue, crowding the rock pools. _Pomacentrus_ of many species, blue, scarlet, black, and golden, abound in Polynesia, and no rock pool in the East Indies is without several forms of this type. The type reaches its greatest development in the south seas. About forty different species of _Pomacentrus_ and _Glyphisodon_ occur in the corals of the harbor of Apia in Samoa. [Illustration: FIG. 315.—Cockeye Pilot, _Glyphisodon marginatus_ (Bloch). Cuba. ] Almost equally abundant are the species of _Glyphisodon_. The "cockeye pilot," or jaqueta, _Glyphisodon marginatus_, green with black bands, swarms in the West Indies, occasionally ranging northward, and is equally common on the west coast of Mexico. _Glyphisodon abdominalis_ replaces it in Hawaii, and the Asiatic _Glyphisodon saxatilis_ is perhaps the parent of both. _Glyphisodon sordidus_ banded with pale and with a black ocellus below the soft dorsal is very common from Hawaii to the Red Sea, and is a food-fish of some importance. _Glyphisodon cœlestinus_ blue, with black bands, abounds in the south seas. The many species of _Amphiprion_ are always brilliant, red or orange, usually marked by one or two cross-bands of creamy blue. _Amphiprion melanopus_ abounds in the south seas. _Azurina hirundo_ is a slender species of lower California of a brilliant metallic blue. All these species are carnivorous, feeding on shrimps, worms, and the like. [Illustration: FIG. 316.—Indigo Damsel fish, _Microspathodon dorsalis_ (Gill). Mazatlan, Mex. ] _Microspathodon_ is herbivorous, the serrated incisors being loosely implanted in the jaws. _Microspathodon dorsalis_, of the west coast of Mexico, is of a deep indigo-blue color, with streamer-like fins. _Microspathodon chrysurus_, of the West Indian coral reefs, black with round blue spots and the tail yellow. This family is probably of recent origin, as few fossils are referred to it. _Odonteus pygmæus_ of the Eocene perhaps belongs to it.