46 



HITCHCOCK'S ANATOMY 



shaped in its general outline, although it is covered and 

 filled with cavities and processes for the protection and 

 proper direction of many of the delicate organs which pass 

 through it to their destination. This bone articulates with 

 all those in the cranium, and five of those in the face, and 

 serves as a point of attachment for twelve pairs of muscles, 

 and is one of the most complicated bones belonging to the 

 human skeleton. 



The last bone of the skull is situated at the base of 



Cribriform Plate. 5, Superior Meatus. A View of the Outside of the Vault of 



G, Superior Turbinated Bone. 7, Middle the Cranium, showing the Sutures. 1, The 



Turbinated Bone. 8, Os Plenum. 9, Sur- Coronal Suture. 2, The Sagittal Suture, 



face for the Olfactory Nerve. 3, The Lambdoidal Suture. 



the front portion of the cranium, between the sockets of 

 the eyes, and behind the root of the nose. It is called the 

 Ethmoid Bone. Its outline is that of a cube, consisting of a 

 perpendicular plate, and two lateral portions. From the 

 fact that it is extremely fragile, owing to the great number 

 of perforations which it contains, it derives its name from the 

 Greek word signifying a sieve. It is so deeply seated that it 

 receives the attachments of no muscles. 



108. Sutures. — The bones of the skull are united by 



Give the shape and position of the Ethmoid bone. Why called Ethmoid? 



