Bones of the Cranium. 



Arl.w. t. Perpend, 

 plate of t. Ethmoid b. 



RamuLu 

 pterygoi 



5. Sphenoid Bone, Os sphenoideum , from before. 



Body. On the anterior surface are two irregular openings, 

 which lead into the sphenoidal sinuses ? and are separated from each 

 other by the Crista sphenoidalis ; this becomes elongated in front, forming 

 the Rostrum sphenoidale. 



The pterygoid processes are formed of two plates, the exter- 

 nal and internal pterygoid plates, Lamina pteryyoidm externa et internet, 

 separated behind by an intervening notch, the Fossa ptcrygoidca ; the inner 

 plate ends in the hamular process, Hamulus ptenjgoideus. Between both 

 plates is the Incisura pterygoidea (Fig. 6). At the base of the pterygoid 

 process is the Vidian canal, running in a horizontal direction, and from 

 whose anterior opening the pterygo-palatine groove, Sulcus pteryyo-pala- 

 tinus, passes in a downward course. 



The Ossicula Bertini or sphenoidal turbinated bones are triangular bones, 

 partially covering the openings of the sphenoidal sinuses, which latter are 

 situated on the anterior wall of the body of the sphenoid bone. 



