=Sutures of the Skull.=--The bones of the skull join each other by means of immovable articulations known as sutures. These sutures are designated by combining the names of the bones between which they are situated: as, =sphenofrontal= suture (=sutura sphenofrontalis=), between the sphenoid and frontal; =nasomaxillary= suture (=sutura nasomaxillaris=), between the nasal and maxillary bones. When a suture joins the two corresponding bones of opposite sides the prefix =inter= is used, as the =intermaxillary= suture (=sutura intermaxillaris=) between the maxillaries. The sutures bounding the parietals have, however, received special names not derived in this manner. The suture caudad of the parietals, separating them from the occipital and interparietal, is known as the =lambdoidal= suture; that between the two parietals is the =sagittal= suture; that separating the parietals and squamous portions of the temporals is the =squamous= suture; that between the parietals and frontals is the =coronal= suture. The suture separating the two frontals also is known as the =frontal= suture, in place of interfrontal.
=Articulations of the Mandible.=--In man the two halves of the mandible are united craniad, so as to form a single bone. In the cat the two halves are separate, but articulate closely at the =symphysis menti= by a thin interarticular cartilage.
The articulation of the mandible at the mandibular fossa of the temporal is covered with a close =articular capsule=. The mandibular fossa is lined with cartilage. A slender ligament passes from the angular process of the mandible caudad to the external auditory meatus, being attached to the latter about 8 millimeters from its medial end. This is the =stylomandibular ligament=.
=Scapula= (Figs. 44 and 45).--The scapula may be described as a flat triangular bone with one angle rounded. It lies beneath the muscles on the lateral face of the thorax near its cranial end. From its lateral surface there projects a flat ridge (Fig. 44, _g_), the =spine= of the scapula. The ventral end of the ridge is free as a curved process, the =acromion= process (Fig. 44, _j_).
[Illustration: FIG. 44.--SCAPULA, LATERAL SURFACE.
_I_, fossa supraspinata; _II_, fossa infraspinata; _III_, fossa subscapularis; _IV_, fossa for teres major. _a_, vertebral border; _b_, coracoid border; _c_, glenoid border; _d_, glenoid angle and fossa; _e_, coracovertebral angle; _f_, glenovertebral angle; _g_, spine; _h_, tuberosity of the spine; _i_, metacromion; _j_, acromion; _k_, supraglenoidal tubercle; _l_, incisura scapulæ; _m_, coracoid process; _n_, groove indicating portion of spine; _o_, _o′_, ridges for attachment of muscle-fibres.]