The suborder acanthini have fins which are always supported by soft rays, while the ventral fins are either wanting, or if present, are under the throat, below or anterior to the pectoral fins, and supported by the pectoral arch. The swim-bladder is sometimes absent, but when present does not communicate, as in the preceding order, with the oesophagus by a duct. This suborder is also divided into two groups, by the presence or absence of ventral fins—apoda and subbrachutta. The most familiar example of the apoda is the sand-eel (ammunlytes) see LAUNCE, ante. The subbrachiata contain the two important families, the gadidce (q.v.), or cod family, comprising the cod (q.v.), haddock (q.v.), ling (q.v.), etc., and the pleuronectldce (q.v.), or fiat fishes (q.v.), comprising the sole (q.v.), plaice (q.v.), halibut (q.v.), brill (q.v.), turbot (q.v.), etc.
The suborder acanaopteri have fins in which one or more of the first rays are unjointed, inflexible, and spiny, and as a rule the exoskeleton being composed of ctenoid scales. The ventral fins are generally beneath or, in advance of the pectorals, and the duct of the air-bladder is always absent. This suborder is divided into pharyn cognathi (q.v.) having the inferior pharyngeal bones anchylosed to form a single bone; and acanthopteri veri, characterized by always having spiny rays in the first dorsal fin, and usually in the first rays of the other fins, while the inferior laryngeal bones are never anchylosed into a single mass. This division is perhaps the most typical of
the teleost fishes containing the percidce, see PERCH, ante; the mugilicke, see MULLET, ante; the scomberidce (q.v.), see also MACKEREL, ante; the gobildce, see Gonv, ante; the Nonnoidai, see BLENNY, ante; and the lophiidce, see ANGLER, ante. Thejeraida ip the most important family, and distinguished by having ctenoid scales, teeth on the polite and vomer, as well as on the jaws, and having from five to seven branchiostegal rays.
The suborder plectognathi are characterized by having the maxillary and premax illary bones immovably connected on each side of the jaw. The endoskeleton is only partially ossified, and the vertebral column remains permanently cartilaginous. The exoskeleton is in the form of ganoid plates, scales, or spines, and there are generally no ventral fins, and the air-bladder has no duct. The most remarkable fishes of this sub division are the trunk fishes (q.v.). See also OSTRACION, ante.
The suborder lophobranchii, (q.v.) is a small group, characterized by a peculiar struc ture of the gills, which are arranged in little tufts upon the branchial arches instead of in comb-like plates, as in the typical bony fishes. The endoskeleton is only partially bony, but the exoskeleton is composed of ganoid plates, and the air-bladder has no duct. Belonging to this suborder are the sea-horses or hippocampida, see HirrocAurus, ante; and the syngnathichr, see Pn-E-Fisir, ante..