THE ENTIKE SKULL 515 



Behind the scaphoid fossa is the irregular opening known as the 

 middle lacerated foramen. It is bounded medially by the basi- 

 sphenoid and basioccipital, in front and laterally by the sloping 

 spheno-petrosal lamina of the alisphenoid, and behind and medially 

 by the apex of the petrous part of the temporal, in which can be seen 

 the anterior end of the carotid canal. Projecting into the anterior 

 medial corner of the lacerated foramen is the vaginal tubercle, just 

 below the posterior opening of the Vidian canal. Above this opening 

 the lingula of the sphenoid is sometimes visible. 



In front of the spheno-petrosal lamina is the foramen ovale, 

 behind and lateral to which are the smaller foramen spinosum and 

 the prominent angular spine. The flattened surface of the sphenoid 

 in front of these foramina is the zygomatic surface of the great wing ; 

 it ends in front at the sphenoidal fissure, or anterior lacerated fora- 

 men, and is separated from the temporal surface of the wing by the 

 infratemporal crest, and from the triangular zygomatic surface of the 

 squamous by part of the squamo-sphenoidal suture. 



Behind this surface of the squamous is the deep, oval glenoid 

 cavity for the condyle of the lower jaw. It is bounded in front by 

 the articular eminence, and behind by the Glaserian fissure, which 

 separates the petrous and squamous from the tympanic plate. The 

 medial edge of the tympanic plate is the vaginal process ; its poste- 

 rior end forms a sheath around the base of the styloid process. The 

 lateral edge, known as the auditory process, is the lower margin of 

 the external auditory meatus. Behind the styloid process is the stylo- 

 mastoid foramen for the facial nerve. The irregular suture between 

 the tympanic plate and the mastoid is the auricular fissure, giving 

 exit to Arnold's nerve. 



The mastoid process is very prominent ; the groove medial to it is 

 the digastric fossa. Near its upper end is the mastoid foramen, 

 and to its medial side is the furrow for the occipital artery. 



The median part of the base of the cranium, anterior to the 

 foramen magnum, is formed of the basioccipital ; it exhibits on the 

 middle line the variable pharyngeal tubercle. 



On either side of the foramen magnum is a flattened occipital 

 condyle. Above the condyle is the anterior opening of the anterior 

 condyloid canal, and behind it, in a fossa, the posterior opening of 

 the inconstant posterior condyloid canal. 



