The cartilage is called the quadrangular cartilage and the bones comprising the septum include the maxillary crest, vomer and the perpendicular plate of the ethmoid.

Above and to the back (posterosuperiorly), the bony nasal septum is composed of the perpendicular plate of the ethmoid bone.

Its posterior margin is connected with the perpendicular plate of the ethmoid; its inferior margin with the vomer and the palatine processes of the maxillae.

The ethmoid has three parts: the cribriform plate, the ethmoidal labyrinth, and the perpendicular plate.

In bony fish the palatine bone consists of the perpendicular plate only, lying on the inner edge of the maxilla.

The ethmoid is ossified in the cartilage of the nasal capsule by three centers: one for the perpendicular plate, and one for each labyrinth.

During the first year after birth, the perpendicular plate and crista galli begin to ossify from a single center, and are joined to the labyrinths about the beginning of the second year.

The cribriform plate is ossified partly from the perpendicular plate and partly from the labyrinths.

The vertical part (perpendicular plate) of the palatine bone is thin, of an oblong form, and presents two surfaces and four borders.

The spine forms part of the septum of the nose, articulating in front with the crest of the nasal bones and behind with the perpendicular plate of the ethmoid.