FIGURE 8 



Section of head of 20 mm. human embryo passing through epistropheus, 

 atlas, and interorbital septum. 



1, Lateral mass of atlas 



2, Caudal tips of condyles 



3, Anterior arch of atlas 



4, Anterior arch of occipital vertebra 



5, Base of densepistrophei 



6, Interorbital septum 



7, Reichert's cartilage 



8, Meckel's cartilage 



9, Manubrium mallei 



10, Ventral tij^s of alae temporales 



642 



