OSTEOLOGY. 37 



lachrymal canal, with the spheno-maxillary fossae by the spheno- 

 palatine foramen, and with the cranium by the olfactory fo- 

 ramina. 



They are each bounded by an outer, inner, upper, and lower 

 wall. 



The outer watt is divided by the middle turbinated process of 

 the ethmoid and the inferior turbinated bone into the superior, 

 middle, and inferior meatuses of the nose. 



The superior meatus, the smallest, has three orifices opening 

 into it 



The posterior ethmoidal cells ; 



The sphenoidal sinuses, opening behind the superior tur- 

 binated bone, and 



The spheno-palatine foramen, for transmission of spheno- 

 palatine vessels and superior nasal and naso-palatine nerves. 



The middle, meatus has two orifices 



The infundibulum, communicating with the frontal sinuses, 

 and through them with the anterior ethmoidal cells, and the 

 orifice of the antrum or maxillary sinus. 



The inferior meatus, the smallest, has two orifices 



The lachrymal canal, for lachrymo-nasal duct, and the an- 

 terior palatine canals, for anterior branches of descending pala- 

 tine arteries (foramina of Stenson) and naso-palatine nerves 

 (foramina of Scarpa). 



The inner wall, or saeptum nasi, is formed by the vomer, 

 vertical plate of the ethmoid, arid the triangular cartilage of the 

 nose, with portions of the following bones: nasal spine of the 

 frontal, rostrum of the sphenoid, and the crests of the nasal, 

 palate, and superior maxillary bones. It is grooved by the naso- 

 palatine and other nerves. 



The upper wall or roof presents the following from before 

 backward : 



The nasal slit in the cribriform plate, for passage of nasal 

 nerve, a branch of ophthalmic; 



The olfactory foramina, for olfactory filaments, and 



O/tenings or orifices posteriorly of the sphenoidal sinuses. 



The lower wall or floor presents from before backward : 



The anterior nasal spine; 



The anterior palatine canals, given above; 



Crest or ridge for vomer; 



^u I ure between superior maxillary and palate-bone, and 



Posterior nasal spine. 



