The quadrate is invariably a conspicuous bone and movably articulating with the cranium and by a special process with the pterygoid.
Premolars compressed, pointed; and the molars with quadrate tuberculated crowns.
Owing to this joint the whole upper beak can be moved up and down with extra facility, according to the shoving forwards or backwards of the palato-pterygo-quadrate apparatus which moves sledge - like upon the cranial basis.
The maxillaries are connected with the distal anterior corner of the quadrate by the thin, splint-like jugal and quadratojugal.
A membranous, or ossified, tube which rises from a pneumatic foramen in the os articulare, on the median side of the articulation, and passes upwards between the quadrate and lateral occipital bone, opening into the cavity of the middle ear.