573 



surface, above the mastoid, the other descending to terminate at the ordinary foramen jugnlare : 

 the anterior canal descends to the base of the zygoma, where it also divides, one division opening 

 on the inner and the other on the outer side of the post-glenoid process. The foramen rotun- 

 dum is blended with the foramen lacerum anterius. The rhinencephalic fossa is narrow but 

 deep. The osseous septum is coextensive with the nasal bones. The maxillo-premaxillary 

 sutures are obliterated, with the exception of a slight trace upon the palate : there is a trace 

 of the nasomaxillary suture ; all the other sutures of the cranium are obliterated. 



This cranium exhibits an instance of symmetrical morbid action, the socket of the first 

 true molar being more or less absorbed on each side. The second true molar differs from 

 that in either of the preceding specimens, by having a columnar process at the internal interval 

 of the two lobes of the crown. 



3448. The lower jaw. 



The socket of the first true molar on the right side has begun to be affected by the ulcera- 

 tive absorption. 



3449. The atlas. 



The anterior articular cavities meet and blend together below. The transverse process is 

 perforated twice by the vertebral artery and twice by canals extending apparently outwards 

 from the neural canal. The transverse process extends from the anterior to the posterior 

 articular surface as a simple ridge very slightly produced outwards. 



3450. The axis. 



The neural canal is widely open above between the atlas and axis. The canal for the 

 vertebral artery hi the axis commences within the neural canal and opens externally at the 

 fore part of the transverse process. The second pair of cervical nerves perforate the fore 

 part of the neural arch. The neural spine is represented by a rough bifid tubercle. The 

 hypapophysis is of a similar form, but is less developed below. 



3451. The third cervical vertebra. 



9 



An accessory pair of processes is developed in this vertebra from the fore part of the sides 

 of the centrum, which descend obliquely downwards and outwards, and represent the plenr- 

 apophyses, the parts answering to the transverse processes of the atlas and axis being the 

 diapophyses. The arterial canals commencing behind at the fore part of the neural canal 

 open anteriorly below the bases of the zygapophyses. 



3452. The fourth cervical vertebra. 



This differs from the foregoing chiefly in the greater size of the pleurapophysis. 



