94 



OSSA PALATI. 



for supporting the back part of the os spongiosum inferius. 

 Along the outside of this plate, the perpendicular fossa made 

 by the posterior palatine nerve is observable. 



At the upper and posterior edge of this nasal plate is a notch, 

 which when applied to the sphenoid bone, forms the spheno- 

 palatine foramen, through which a nerve, artery, and vein pass 

 to the nostril ; this notch forms two processes on the posterior 

 part of the bone, the inferior of which is in contact with the 

 internal plate of the pterygoid process of the sphenoidal bone, 

 and has, therefore, been called by some French anatomists, the 

 pterygoid apophysis of the os palati. The superior and anterior 

 portion is the proper orhitar process of this bone, which is 

 Fig. 21.* situated at the posterior part of the lower 

 surface of the orbit, and forms a portion 

 of it. This process of the os palati is 

 hollow ; and its cavity generally com- 

 municates with the contiguous cell of the 

 OS ethmoides. It has several surfaces, 

 one of which is to be found in the orbit, 

 and another in the zygomatic fossa. 



The palate square part of the palate 

 bone, and its pterygoid process, are firm 

 and strong, with some cancelli ; but the 

 nasal plate, and orbitar processes, are very thin and brittle. 



The palate bones are joined to the maxillary, by the fore 

 edges of the palate square bones ; by their thin nasal plates, 

 and part of their orbitary processes, to the same bones ; by 

 their pterygoid processes, and back part of the nasal plates, to 



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* The perpendicular plate of the palate bone seen upon its external or spheno- 

 maxillary surface. 1. The rough surface of this plate, which articulates with 

 the superior maxillary bone. 2. The posterior palatine canal, completed by the 

 tuberosity of the superior maxillary bone. The rough surface to the left of the 

 canal (2) articulates with the iniernal pterygoid plate. 3. The sphcno-palatine 

 or lateral nasal foramen. 4, 5, 6. The orbital portion of the perpendicular plate. 

 4. The pterygoid apophysis or spheno-maxillary facet of this portion. 5. Its 

 orbital facet or process. 6. Its maxillary facet, to articulate with the superior 

 maxillary bone. 7. The sphenoidal portion of the perpendicular plate. 8. The 

 pterygoid process or tuberosity of the bone. 



