677 



sphenoidal angle has disappeared. The axis of Hie nasal septum is 

 no longer vertical to the base of the skull, it has rotated, so that 

 it forms an angle of 115° with the axis of the base of the skull. 

 Fig. 8. Embryo of 25 mm. The canalis Hypophyseos is closed, 

 basal plate and prechordal plate have coalesced completely. The 

 septum nasale has rotated further, and is inclined to the base of 

 the skull at an angle of 130°, the part of this base to which the 

 septum nasale is attached is bent slightl}- ujiwards, which is the 

 iirst indication of the developing ethmoidal angle. 



Fig. 9. 



Fig. 10. 



Fig. 9. Embryo of 35 mm. Three centra of ossification have 

 appeared in the basis crajiii for the Basioccipitale, the Basispheiioid 



