OSSA NASI. 89 



and the sockets of the teeth, particularly those of the second 

 molar tooth ; occasionally the fangs of the tooth enter the cavity. 



The internal or nasal surface of this bone forms a large part 

 of the cavity of the nose, and is concave. At the root of the 

 nasal process is a ridge, for supporting the anterior end of the 

 lower turbinated bone. The nasal process seems continued 

 into the cavity of the nose, and forms a portion of the orifice 

 of the canal for the lachrymal duct, which is on the external 

 side of this cavity, near its anterior opening, and under the 

 lower turbinated bone. The orifice in this bone by which the 

 antrum maxillare communicates with the nose, is very large ; 

 but it is reduced to a small size, by a plate from the ethmoid 

 bone, by a portion of the os palati, and of the lower spongy 

 bone, each of which covers a part of it. 



The three foramina are, 1st. The infra-orbitary foramen 

 already described. 2d. The foramen incisivum or anterior 

 palatine hole, which passes through the palatine process, from 

 the nose to the mouth. In the nose it forms generally two 

 foramina, which unite and form but one in the mouth, imme- 

 diately behind the middle incisor teeth. This foramen is 

 closed by the soft parts during life, and transmits a branch of 

 the spheno-palatine nerve from each side, which runs on the 

 septum narium, and joining at the lower part of the canal with 

 its fellow, they unite, and, according to M. Cloquet,* form a 

 ganglion. 3d. The posterior palatine foramen, which is formed 

 by this bone, and by the os palati, on each side, is situated in 

 the suture which joins them to each other, and transmits to the 

 palate a branch of the upper maxillary nerve. 



This bone is united to the frontal, nasal, unguiform, ethmoid 

 and malar bones, above ; to the ossa palati behind ; to the cor- 

 responding bone, on the opposite side ; and to the inferior spongy 

 bone, in the cavity of the nose. 



Ossa Nasi. 



The ossa nasi are so named from their prominent situation 



* This ganglion, though it varies in size, is readily found. I always exhibit 

 it ia the course of my lectures. — p. 



8* 



