The remains of bony fishes have been collected at many localities in Texas, and fossils of this type have been found primarily in rocks of [Cretaceous] age but have been reported from other rocks as well. Fish fossils are more commonly found in the form of teeth ([Pl. 37]), vertebrae, scales, and an occasional well-preserved skeleton.

Plate 37

SHARK TEETH × 1

CONODONTS
(GREATLY ENLARGED)

PRIMITIVE ARMORED FISH
PLACODERM ([DEVONIAN])
× ½

Conodonts ([Pl. 37]) are small, amber-colored, tooth-like fossils which are believed to represent the teeth of some type of extinct fish. Although geologists do not know a great deal about the origin of these strange fossils they are of value in micropaleontology. Conodonts have been reported from several [Paleozoic] formations in Texas and are useful guide fossils in some areas.

Superclass Tetrapoda