EXTERNAL SURFACE OF THE SKULL. 



63 



canine fossae ; and external to the canine fossae are the prominences of the cheeks, 

 formed by the anterior inferior parts of the malar bones. The lower jaw completes 

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

 orbital foramen or notch in the superior margin of the orbit, the infraorbital 

 foramen below the inferior margin of the orbit, the mental foramen of the lower jaw, 

 and the small malar canal of the malar bone. 



The anterior nasal aperture is often markedly unsymmetrical, one half of the opening being 

 broader and shorter, while on the other side it is narrower and more deeply excavated below. 

 This is associated with a corresponding deviation of the cartilaginous part of the nose, which 

 points towards the side on which the wider half of the aperture is placed. (H. Welcker, " Die 

 Asymmetrien der Nase und des Nasenskeletes," Stuttgart, 1882.) 



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

 direeted forwards and slightly outwards, their inner walls being nearly parallel, and 



Fig. 65. FRONT VIEW OF MALE SKULL AT 

 ABOUT TWENTY TEAKS. (Allen Thomson.) \ 



1 . frontal eminence ; 2, glabella, between the 

 superciliary ridges, and above the transverse 

 suture of union with the nasal and superior 

 maxillary bones ; 3, orbital arch near the 

 supraorbital notch ; 4, orbital surface of 

 great wing of sphenoid, between the sphe- 

 noidal and the spheno-maxillary fissures ; 

 5, anterior nasal aperture, within which are 

 seen in shadow the vomer and the turbinate 

 bones ; 6, superior maxillary bone at the 

 canine fossa above the figure is the infra- 

 orbital foramen ; 7, incisor fossa ; 8, malar 

 bone ; 9, symphysis of Jower jaw ; 10, mental 

 foramen ; 11, vertex, near the coronal suture ; 

 12, temporal fossa ; 13, zygoma; 14, mastoid 

 process ; 15, angle of the jaw ; 16, mental 

 protuberance. In this skull there are fourteen 

 teeth in each jaw, the wisdom teeth not having 

 yet appeared. 



their outer walls diverging so as to 



be nearly at right angles to each 



other. The roof of each orbit is 



formed by the orbital plate of the 



frontal and the small wing of the 



sphenoid ; the floor (fig. 66) by the 



malar and superior maxillary bones, 



and by the small orbital surface of 



the palate bone at the back part ; 



the inner wall (fig. 69) by the nasal 



process of the superior maxilla, the lachrymal, the ethmoid and body of the 



sphenoid ; .and the outer wall by the orbital surfaces of the malar bone and great 



wing of the sphenoid. The spJienoidal fissure (foramen lacerum orbitale) at 



its inner extremity occupies the apex of the orbit, -while its outer and narrower 



part lies between the roof and the external wall. The optic foramen is internal 



and superior to the sphenoidal fissure. In the angle between the external wall 



and the floor is the spheno-maxillary fissure, bounded by the sphenoid, palate, 



superior maxillary, and malar bones, and leading into the spheno-maxillary fossa at 



its back part, into the zygomatic fossa at its fore part. Passing forwards from the 



margin of the spheno-maxillary fissure is the commencement of the infraorbital 



canal, grooving the posterior part of the floor of the orbit. On the inner wall in 



