48 OSTEOLOGY, OR ANATOMY OF OSSEOUS SYSTEM 



horizontally outward on a level with the forepart of the superior 

 surface of the body; the extremity of each is pointed and comes 

 almost into contact with the great wing. The inferior surface 

 forms the upper boundary of the sphenoidal fissure and part 

 of the roof of the orbit. The anterior border articulates with 

 the orbital plate of the frontal; the posterior is free, and forms 

 the boundary between the anterior and middle fossae of the 

 skull, and terminates internally in the anterior clinoid process. 

 Between this clinoid process and the olivary eminence is a 

 semicircular notch in which the carotid groove ends. The 

 optic foramen perforates the base of the wing, the parts above, 

 and below being called its roots. 



The great or temporal wings project out and up from the 

 sides of the body; the back part of each is horizontal and fills 

 the angle between the squamous and petrous portions of the 

 temporal; from its extremity projects downward the spinous 

 process. The forepart is vertical and three-sided, and lies 

 between the cranial cavity, the orbit, and temporal fossa. 



The cerebral surface is concave, and forms part of the middle 

 fossa of the skull. 



The external surface (temporozygomatic) is divided by the 

 infratcmporal crest into a lower part looking down into the 

 zygomatic fossa, and an upper part looking out into the tem- 

 poral fossa. 



The anterior surface looks forward and inward, and consists 

 of the orbital plate for the external wall of the orbit, and of 

 a smaller portion above the pterygoid process which looks 

 into the sphenomaxillary fossa and is perforated by the fora- 

 men rotundum. 



The posterior border near the body bounds the foramen 

 lacerum, and in its lateral part articulates with the petrous, 

 forming a groove beneath for the cartilaginous portion of the 

 Eustachian tube. The external border, commencing at the 

 spinous process, articulates with the squamous, and above 

 it overlaps the anterior inferior angle of the parietal bone. 

 In front of this is a triangular surface formed by the upper 

 margins of the cerebral, orbital, and temporal surfaces. The 

 anterior margin articulates above with the malar; below this 

 is a free horizontal edge separating the zygomatic from the 

 sphenomaxillary surface. Above and internally the orbital 

 and cerebral surfaces meet at a sharp border, which forms 



