56 BONES OF THE HEAD. 



skeleton of the face below. The foramina in this region, on each side, are 

 the supra-orbital foramen or notch in the superior margin of the orbit, the 

 infra-orbital foramen below the inferior margin of the orbit, the mental 

 foramen of the lower jaw, and the small irregular foramina of the malar 

 bone. 



The orbits are pyramidal fossae, irregularly quadrilateral, with their bases 



Fig. 50. 



Fig. 50. SECTION OP THE SKULL OP A MAN OP MIDDLE AGE, IN TWO PLANES, ONE OP 

 WHICH PASSES VERTICALLY THROUGH THE LEFT ORBIT TO THE INNER SIDE OP ITS 

 MIDDLE, AND THE OTHER OBLIQUELY FROM BEHIND THE ORBIT, BACKWARDS AND 

 OUTWARDS, THROUGH THE TYMPANUM AND MASTOID PROCESS, AND TO THE OUTSIDE 

 OP THE FORAMEN ROTUNDUM AND FORAMEN OVALE. 



1, section of the frontal Lone in the roof of the orbit ; 2, left nasal bone ; 3, nasal 

 process of the superior maxillary bone ; 4, left lachrymal bone, and in front the groove 

 of the nasal duct ; 5, placed on the os planum of the ethmoid bone, below the anterior of 

 the ethmoid foramina ; 6, is placed below the root of the lesser wing of the sphenoid 

 bone, between the optic foramen and the posterior internal orbital or ethmoid foramen, 

 and close to the foramen lacerum orbitale ; 7, floor of the orbit, formed by orbital plate of 

 the superior maxillary bone the figure is placed close to the inside of the infra-orbital 

 groove ; 8, is placed on the orbital plate of the palate bone, in front of and above the 

 spheno-pfc^tlne foramen and spheno-maxillary fossa ; 9, marks the upper extremity of 

 the posterior palatine (or palato-maxillary) canal ; towards 11 in the fossa is the opening 

 backwards of the Vidian canal; 10, the cranial opening of the foramen rotundum its 

 anterior opening is seen in the spheno-maxillary fossa ; 11, section of the great wing of 

 the sphenoid bone outside the round and oval foramina ; 12, is placed close to and 

 between the spinous and oval foramina; 13, is placed on the anterior surface of the 

 petrous bone, near the apex, or in the fossa of the Gasserian ganglion ; towards the orbit 

 are seen the foramen lacerum anterius, sigmoid groove of the internal carotid artery, and 

 pituitary fossa, below the figure and externally the hiatus Fallopii ; 14, the pituitary 

 fossa, with the anterior and posterior clinoid processes ; 15, section of the petrous bone 

 above the labyrinth ; two of the semicircular canals are opened ; immediately below is 

 the tympanum. The inner wall is seen with the promontory, fenestra ovalis and pyramid 

 in shadow ; forwards, at x , the opening of the tympanum towards the Eustachian canal, 

 and backwards, below 16, the opening into the mastoid cells ; 17, left styloid process 

 that of the right side is seen in perspective below the skull, close by the occipital condyle; 

 18, tuberosity of the superior maxilla; 19, canine fossa; 20, nasal notch and anterior 

 nasal spine ; 21, inner wall of the antrum seen by the removal of its outer wall ; above 

 the figure is the maxillary process of the inferior turbinated bone, and over that an 

 irregular fissure, viz., the opening of the antrum into the middle meatus of the nose, and 

 above that the uncinate process of the ethmoid bone. 



