MALAR BONE. 



87 



Bnarln passed tA 

 Te'mfffro-Mala,r C-aivds 



THE MALAR BONES. 



The Malar Bones are two small quadrangular bones, situated at the upper and 

 outer part of the face, forming the prominence of the cheek, part of the outer wall 

 and floor of the orbit, and part of the temporal and zygomatic fossae. Each bone 

 presents for examination an external and an internal surface ; four processes, the 

 frontal, orbital, maxillary, and zygomatic ; and four borders. The external surface 

 (fig. 49) is smooth, convex, perforated near its centre by one or two small 

 apertures, the malar foramina, for the passage of nerves and vessels, covered 

 by the Orbicularis palpebrarum 



muscle, and affords attachment Fig. 49. Left Malar Bone. Outer Surface. 



to the Zygomaticus major and 

 Zygomaticus minor muscles. 



The internal surface (fig. 50), 

 directed backwards and inwards, 

 is concave, presenting internally 

 a rough triangular surface, for 

 articulation with the superior 

 maxillary bone ; and externally, 

 a smooth concave surface, which 

 forms the anterior boundary of 

 the temporal fossa above, wider 

 below, where it forms part of 

 the zygomatic fossa. This sur- 

 face presents, a little above its 

 centre, the aperture of one or two 

 malar canals, and affords attach- 

 ment to part of two muscles, the 

 Temporal above, and the Masse- 

 ter below. Of the four processes, 

 ihefrontalis thick and serrated, 

 and articulates with the external 

 angular process of the frontal 

 bone. The orbital process is a 

 thick and strong plate, which 

 projects backwards from the 

 orbital margin of the bone. Its 

 upper surface, smooth and con- 

 cave, forms, by its junction with 

 the great ala of the sphenoid, 

 the outer wall of the orbit. Its 

 under surface, smooth and con- 

 vex, forms part of the temporal 

 fossa. Its anterior margin is 

 smooth and rounded, forming 

 part of the circumference of the 

 orbit. Its superior margin, rough, 

 and directed horizontally, arti- 

 culates with the frontal bone 

 behind the external angular pro- 

 cess. Its posterior margin is rough and serrated, for articulation with the sphenoid : 

 internally it .is also serrated for articulation with the orbital surface of the superior 

 maxillary. At the angle of junction of the sphenoidal and maxillary portions, a 

 short rounded non-articular margin is sometimes seen ; this forms the anterior 



Fig. 50. Left Malar Bone. Inner Surface. 



