26 ANATOMY. 



ORBITAL PROCESS,' triangular in shape, large and hollow. It has 



Three Articular Surfaces, for the sup. maxillary, sphenoid, and ethmoid. 



Two Free Surfaces, the orbital forming part of the floor of the orbit, tha 

 external aiding to form the zygomatic fossa. 



Rounded Border, forms a part of the spheno-maxillary fissure. 

 SPHENOIDAL PROCESS,/ projects backwards, articulates superiorly with the 



body of the sphenoid, and externally with the pterygoid process of the 



sphenoid. On its upper surface is a 



Groove, which assists in forming the ptery go-palatine canal. 



Inner Surface, forms part of the outer wall of the nasal fossa. 



Describe its articulations, development, and muscles. The palate 

 articulates with 6 bones, the sphenoid, ethmoid, vomer, superior maxillary, 

 inferior turbinated, and its fellow palate bone. It is developed by one centre at 

 the junction of the two plates. There are 5 muscles attached to it, the azygos 

 uvulae, internal and external pteiygoids, superior constrictor, and tensor palatL 



THE INFERIOR TURBINATED BONES. 



Describe them. They are 2 thin curved osseous plates situated in the 

 nasal fossae, their convex surfaces presenting inwardly. Each bone is attached 

 above to the inferior turbinated crests of the superior maxillary and palate 

 bones, and presents the following, viz. 



Lachrymal Process? aiding to form the nasal 

 duct, by articulation with the lachrymal and 

 superior maxillary bones. 



Ethmoidal Process, 1 articulating with the unci- 

 form process of the ethmoid, thus helping to 

 partially close the aperture of the antrum. 

 Maxillary Process,* also helps to partially close the aperture of the antrum, 



by hooking 7 over the lower edge of that orifice. 



Free Border? below, coming to about ^ inch above the floor of the nose. 

 Name its articulations, centres, and muscles. The inferior turbinated 

 articulates with 4 bones, the ethmoid, lachrymal, palate, and superior max- 

 illary. It is developed by one centre, and has no muscles attached to it. 



THE VOMER. 



Describe it. The vomer (plough-share) forms the postero-inferior part 

 FIG. 10. of the nasal septum, but is usually bent to one 



side. Its 



Superior Border^ 2 has a groove and two alas 

 or wings, for articulation with the rostrum 

 and vaginal processes of the sphenoid bone. 



