The angle of the mandible, which may be either inverted or everted, is marked by rough, oblique ridges on each side, for the attachment of the masseter laterally, and the pterygoideus internus ( medial pterygoid muscle ) medially; the stylomandibular ligament is attached to the angle between these muscles.
12.
On its medial wall, at the forepart, is a small circular depression, the recessus sph�ricus, which is perforated, at its anterior and inferior part, by several minute holes ( macula cribrosa media ) for the passage of filaments of the acoustic nerve to the saccule; and behind this depression is an oblique ridge, the crista vestibuli, the anterior end of which is named the pyramid of the vestibule.
13.
Its " medial surface " forms part of the lateral wall of the nasal cavity; at its upper part is a rough, uneven area, which articulates with the ethmoid, closing in the anterior ethmoidal cells; below this is an oblique ridge, the ethmoidal crest, the posterior end of which articulates with the middle nasal concha, while the anterior part is termed the agger nasi; the crest forms the upper limit of the atrium of the middle meatus.