(_plesios_, Gr., near, almost; _podos_, Gr., foot)
Labyrinthodontia having limbs provided with digits, but
retaining posterior flanges on axial bones as in
Rhipidistia, without joint-structure at elbow and wrist
essential for terrestrial locomotion; neurocranium having
separate otico-occipital section, large notochordal canal,
no occipital condyle, as in Rhipidistia; nares separate from
rim of mouth; pectoral girdle anthracosaurian; vertebrae
having U-shaped intercentrum and paired, but large,
pleurocentra.
Probably associated with the characters of the order, as given above,
are the connection of pectoral girdle with skull, and the presence of a
tympanic membrane, the stapes functioning in both sound-transmission
and palatoquadrate suspension.