THE STHUOTUKE OF THE III MAN SKULL. 



117 



constitute a continuous series, from the occipital foramen to 

 the anterior extremity of the nasal passage, which, as it forms 

 the common centre or axis, not only for the bones of the brain- 



Fig. 50. 



iWA%] 



Fisr. 50. — Longitudinal and veitical section of a Human Skull. — * The sella turcica. An. 

 The position of the superior and posterior vertical semicircular canals. /., II., V., 

 VIII., IX. The exit of the olfactory, optic, third division of the fifth, eighth, and 

 ninth nerves. Vo., the Vomer. 



case or cranium proper, but also for those of the face, may be 

 termed the Cranio-facial axis. 



It will be useful to divide this axis into two portions, — a 



