Suborder Chromides.—The suborder Chromides contains spiny-rayed fishes similar to the perch-like forms in most regards, but strikingly distinguished by the complete union of the lower pharyngeal bones, as in the Holconoti and Pharyngognathi, and still more remarkably by the presence of but one nasal opening on each side. In all the perch-like fishes and in nearly all others there are two nasal openings or nostrils on each side, these two entering into the same nasal sac. In all the Chromides the lateral line is incomplete or interrupted, and the scales are usually large and ctenoid.

The Cichlidæ.—The suborder Chromides includes two families, Cichlidæ, and Pomacentridæ. The Cichlidæ are fresh-water fishes of the tropics, characterized by the presence of three to ten spines in the anal fin. In size, color, appearance, habits, and food value they bear a striking resemblance to the fresh-water sunfishes, or Centrarchidæ, of the eastern United States. This resemblance is one of analogy only, for in structure the Cichlidæ have no more in common with the Centrarchidæ than with other families of perch or bass. The numerous species of Cichlidæ are confined to tropical America and to corresponding districts in Africa and western Asia. Tilapia nilotica abounds in the Nile. Tilapia galilæa is found in the river Jordan and the Lake of Galilee. This species is supposed to form part of the great draught of fishes recorded in the Gospels, and a black spot on the side is held to commemorate the touch of Simon Peter. Numerous other species of Cichlidæ, large and small, abound in central Africa, even in the salt ditches of the Sahara.

The species of Cichla, especially Cichla ocellaris, of the rivers of South America, elongate and large-mouthed, bear a strong analogy to the black bass of farther north. A vast number of species belonging to Heros, Acara, Cichlasoma, Geophagus, Chætobranchus, and related genera swarm in the Amazon region. Each of the large rivers of Mexico has one or more species; one of these, Heros cyanoguttatus, occurs in the Rio Grande and the rivers of southern Texas, its range corresponding with that of Tetragonopterus argentatus, just as the range of the whole family of Cichlidæ corresponds with that of the Characinidæ. No other species of either family enters the United States. A similar species, Heros tetracanthus, abounds in the rivers of Cuba, and another, Heros beani, called the mojarra verde, in the streams of Sinaloa. In the lakes and swamps of Central America Cichlidæ and Characinidæ are very abundant. One fossil genus is known, called Priscacara by Cope. Priscacara clivosa and other species occur in the Eocene of Green River and the Great Basin of Utah. In this genus vomerine teeth are said to be present, and there are three anal spines. None of the living Cichlidæ have vomerine teeth.

The Damsel-fishes: Pomacentridæ.—The Pomacentridæ, called rock-pilots or damsel-fishes, are exclusively marine and have in all cases but two anal spines. The species are often very brilliantly colored, lustrous metallic blue and orange or scarlet being the prevailing shades among the bright-colored species. Their habits in the reef pools correspond very closely with those of the Chætodontidæ. With the rock-pilots, as with the butterfly-fishes, the exceeding alertness and quickness of movement make up for lack of protective colors. With both groups the choice of rocky basins, crevices in the coral, and holes in coral reefs preserves them from attacks of enemies large enough to destroy them. In Samoa the interstices in masses of living coral are often filled with these gorgeous little fishes. The Pomacentridæ are chiefly confined to the coral reefs, few ranging to the northward of the Tropic of Cancer. Sometimes the young are colored differently from the adult, having sky-blue spots and often ocelli on the fins, which disappear with age. But one species Chromis chromis, is found in the Mediterranean. Chromis punctipinnis, the blacksmith, is found in southern California, and Chromis notatus is the common dogoro of Japan. One of the largest species, reaching the length of a foot, is the Garibaldi, Hypsypops rubicundus, of the rocky shores of southern California. This fish, when full grown, is of a pure bright scarlet. The young are greenish, marked with blue spots. Species of 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.

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.

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.

Suborder Pharyngognathi.—The wrasses and parrot-fishes, constituting the group called Pharyngognathi (φαρύγξ, gullet; γνάθος, jaw), by Johannes Müller, have the lower pharyngeal bones much enlarged and solidly united, their teeth being either rounded or else flat and paved. The nostrils, ventral fins, pectoral fins and shoulder-girdle are of the ordinary perch-like type. The teeth are, however, highly specialized, usually large and canine-like, developed in the jaws only, and the gills are reduced in number, 3½ instead of 4, with no slit behind the last half gill. The scales are always cycloid and are usually large. In the tropical forms the vertebræ are always twenty-four in number (10 + 14), but in northern forms the number is largely increased with a proportionate increase in the number and strength of the dorsal spines. All the species are strictly marine, and the coloration is often the most highly specialized and brilliant known among fishes, the predominant shade being blue.

All are carnivorous, feeding mainly on crustaceans and snails, which they crush with their strong teeth, there being often a strong canine at the posterior end of the premaxillary, which holds the snail while the lower jaw acts upon it. The species are very numerous and form the most conspicuous feature in the fish markets of every tropical port. They abound especially in the pools and openings in the coral reefs. All are good for food, though all are relatively flavorless, the flesh being rather soft and not oily.

The Wrasse Fishes: Labridæ.—The principal family is that of the Labridæ, characterized by the presence of separate teeth in the front of the jaws. Numerous fossil species are known from the Eocene and Miocene. Most of these are known only from the lower pharyngeal bones. Labrodon is the most widely diffused genus, probably allied to Labrus, but with a pile of successional teeth beneath each functional tooth. The species are mostly from the Miocene.

The northern forms of Labridæ are known as wrasse on the coasts of England. Among these are Labrus bergylta, the ballan wrasse; Labrus viridis, the green wrasse; Labrus ossiphagus, the red wrasse; and Labrus merula, the black wrasse. Acantholabrus palloni and Centrolabrus exoletus have more than three anal spines. The latter species, known as rock cook, is abundant in western Norway, as far north as Throndhjem, its range extending to the northward beyond that of any other Labroid. Allied to these, on the American coast, is the tautog or blackfish, Tautoga onitis, a common food-fish, dusky in color with excellent white flesh, especially abundant on the coast of New England. With this, and still more abundant, is the cunner or chogset, Tautogolabrus adspersus, greenish-blue in color, the flesh being also more or less blue. This fish is too small to have much value as food, but it readily takes the hook set for better fishes.

In the Mediterranean are found many species of Crenilabrus, gaily colored, each species having its own peculiar pattern and its own arrangement of inky spots. Among these are Crenilabrus mediterraneus, Crenilabrus pavo, and Crenilabrus griseus. With these are the small species called Ctenolabrus rupestris, the goldsinny, much like the American cunner, and the long-nosed Symphodus scina.

Of the many West Indian species we may notice the Capitaine or hogfish, Lachnolaimus maximus, a great fish, crimson in color, with its fin spines ending in long streamers; Bodianus rufus, the Spanish ladyfish or pudiano, half crimson, half golden. Halichæres radiatus, the pudding-wife (a mysterious word derived from "oldwife" and the Portuguese name, pudiano), a blue fish handsomely mottled and streaked. Of the smaller species, Clepticus parræ, the janissary, with very small teeth, Halichœres bivittatus, the slippery-dick, ranging northward to Cape Hatteras, and Doratonotus megalepis, of an intense grass-green color, are among the most notable. The razor-fish, Xyrichthys psittacus, red, with the forehead compressed to a sharp edge, is found in the Mediterranean as well as throughout the West Indies, where several other species of razor-fish also occur.

Scarcely less numerous are the species of the Pacific Coast of America. Pimelometopon pulcher, the redfish or fathead of southern California, reaches a length of two feet or more. It abounds in the broad band of giant kelp which lines the California coast and is a food-fish of much importance. The female is dull crimson. In the male the head and tail are black and on the top of the head is developed with age a great adipose hump. A similar hump is found on the adult of several other large labroids. Similar species on the coast of South America, differing in color and size of scales, are Pimelometopon darwini, Trochocopus opercularis, and Bodianus diplotænia. The señorita, Oxyjulis californica, is a dainty cream-colored little fish of the California coast, Halichœres semicinctus, the kelpfish, light olive, the male with a blue shoulder bar, is found in southern California. On the west coast of Mexico are numerous species of Thalassoma, Halichœres, Pseudojulis, Xyrichthys and Iniistius, all different from the corresponding species in the West Indies, and equally different from the much greater variety found in Hawaii and in Samoa. About the Polynesian and West Indian islands abound a marvelous wealth of forms of every shade and pattern of bright colors—blue, green, golden, scarlet, crimson, purple—as if painted on with lavish hand and often in the most gaudy pattern, although at times laid on with the greatest delicacy. The most brilliant species belong to Thalassoma and Julis, the most delicately colored to Stethojulis and Cirrhilabrus. In Gomphosus the snout is prolonged on a long slender tube. In Cheilio the whole body is elongate. In Iniistius the first two dorsal spines form a separate fin, the forehead being sharp as in Xyrichthys. Other widely distributed genera are Anampses, Lepidaplois, Semicossyphus, Duymæria, Platyglossus, Pseudolabrus, Hologymnosus, Macropharyngodon, Coris, Julis, Hemipteronotus, Novaculichthys, Cheilinus, Hemigymnus, and Cymolutes. Halichœres is as abundant in the East Indies as in the West, one of its species Halichœres pæcilopterus being common as far north as Hakodate in Japan. In this species as in a few others the sexes are very different in color, although in most species no external sexual differences of any sort appear. In the East Indian genus, Pseudocheilinus, the eye is very greatly modified. The cornea is thickened, forming two additional lens-like structures.

The small family of Odacidæ differs from the Labridæ in having in each jaw a sharp cutting edge without distinct teeth anteriorly, the pharyngeal teeth being pavement-like. The scales are small, very much smaller than in the Scaridæ, the body more elongate, and the structure of the teeth different. The species are mostly Australian, Odax balteatus being the most abundant. It is locally known as kelpfish.

In the Siphonognathidæ the teeth are much as in the Odacidæ, but the body is very elongate, the snout produced as in the cornet-fishes (Fistularia), and the upper jaw ends in a long skinny appendage. Siphonognathus argyrophanes, from Australia, reaches a length of sixteen inches.

The Parrot-fishes: Scaridæ.—The parrot-fishes, or Scaridæ, are very similar to the Labridæ in form, color, and scales, but differ in the more or less complete fusion of the teeth, a character which varies in the different genera.

Of these the most primitive is Calotomus, confined to the East Indies and Polynesia. In this genus the teeth are united at base, their tips free and imbricated over the surface of the jaw.

The species are dull in color, reddish or greenish. Calotomus japonicus is the Budai or Igami of Japan. Calotomus sandwichensis and Calotomus irradians are found in Hawaii, and Calotomus xenodon on the off-shore islands of Mexico. In Calotomus the dorsal spines are slender. In Scaridea (balia) of the Hawaiian Islands the first dorsal is formed of pungent spines as in Sparisoma.

Cryptotomus of the Atlantic is also a transitional group having the general characters of Sparisoma, but the anterior teeth more separate. The several species are all small and characteristic of the West Indian fauna, one species, Cryptotomus beryllinus, ranging northward to Long Island.

In the large genus Sparisoma the teeth are more completely joined. In this group, which is found only in the tropical Atlantic, the lower pharyngeals are broader than long and hexagonal. The teeth of the jaws are not completely united, the dorsal spines are pungent, the lateral line not interrupted, and the gill membranes broadly united to the isthmus.

Of the numerous species the dull-colored Sparisoma flavescens is most abundant in the West Indies and ranges farther north than any other. Sparisoma cretense, the Scarus of the ancients, is found in the Mediterranean, being the only member of the family known in Europe and the only Sparisoma known from outside the West Indian fauna.

Other West Indian species are the red parrot-fish, Sparisoma abildgaardi, Sparisoma xystrodon, Sparisoma hoplomystax, the last two being small species about the Florida Keys, and the handsome Sparisoma viride from the West Indies.

Scarus is the great central genus of parrot-fishes. Its members are especially abundant in Polynesia and the East Indies, the center of distribution of the group, although some extend their range to western Mexico, Japan, the Red Sea, and Australia, and a large number are found in the West Indies. Most of them are fishes of large size, but a few, as the West Indian Scarus croicensis, reach the length of less than a foot, and other still smaller species (Scarus evermanni, Scarus bollmani) are found only in water of considerable depth (200 fathoms).

The genus Scarus is characterized by not only the almost complete fusion of its teeth, but by numerous other characters. Its lower pharyngeals are oblong and spoon-shaped, the teeth appearing as a mosaic on the concave surface. The gill-membranes are scarcely united to the narrow isthmus, the lateral line is interrupted, the dorsal spines are flexible, and there are but few scales on the head. These, as well as the scales of the body, are always large. The most highly specialized of its species have the teeth deep blue in color, a character which marks the genus or subgenus Pseudoscarus. Of the species of this type, the loro, Pseudoscarus cœlestinus, and the more abundant guacamaia, Pseudoscarus guacamaia (fig. 215 vol. I) of the West Indies, are characteristic forms. The perrico, Pseudoscarus perrico of the west coast of Mexico, and the great blue parrot-fish, or galo, of Hawaii and Samoa, Pseudoscarus jordani, belong to this type. Pseudoscarus jordani was formerly tabu to the king in Hawaii, and its brilliant colors and toothsome flesh (when eaten raw) made it the most highly valued fish at the royal banquets of old Hawaii. It still sells readily at a dollar or more per pound. To this type belong also the blue parrot-fish, Pseudoscarus ovifrons, of Japan. In the restricted genus Scarus proper the teeth are pale. The great blue parrot-fish, of the West Indies, Scarus cœruleus, belongs to this group. This species, deep blue in color, reaches a large size, and the adult has a large fleshy hump on the forehead. Lesser parrot-fish with pale teeth and with showy coloration are the West Indian species Scarus tæniopterus, Scarus vetula, Scarus croicensis, etc.

Very many species of both Scarus and Pseudoscarus, green, blue, red-brown, or variegated, abound about the coral reefs of Polynesia. About twenty-five species occur in Samoa. Pseudoscarus latax and P. ultramarinus being large and showy species, chiefly blue. Pseudoscarus prasiognathus is deep red with the jaws bright blue.

Fossil species referred to Scarus but belonging rather to Sparisoma are found in the later Tertiary. The genera Phyllodus, Egertonia, and Paraphyllodus of the Eocene perhaps form a transition from Labridæ to Scaridæ. In Paraphyllodus medius the three median teeth of the lower pharyngeals are greatly widened, extending across the surface of the bone.