A sub order of plectognath fishes, represented only by the ostracionts or trunk-fishes, having the body covered with a solid coat of mail, no spinous dorsal fin, and teeth in the jaws. It contains only the family <em>Ostraciontidæ</em>, thus contrasted with the <em>Sclerodermi</em> and the <em>Gymnodontes.</em> See cut under <internalXref urlencoded="cow-fish">cow-fish</internalXref>.
User Defined Definitions
"extinct group of armored jawless vertebrates; taxonomy is not clear"