546 ANATOMY IN A NUTSHELL. 



major muscles, as it passes over the clavicle a few fibers may be attached to it. 

 Insertion. — Into the fascia extending from the angle of the mouth to 

 the angle of the jaw, also into the inferior maxillary bone below the mental 

 foramen. 



A.CTION. Helps to depress the lower jaw. 



Nerve Supply. — The inframaxillary division of the seventh. 

 Blood Supply. — Branches of the external carotid artery. 

 15. Buccinator which has been described on page 540. 



LESSON CLXXXV. 

 [nferioe Turbinated Bone. (Plates CCLX-CCLXIV.) 



The inferior turbinated bone, which is situated in the nasal fossa along its 

 outer wall, is curved upon itself. It has two surfaces, two borders, two ex- 

 tremities, and three processes. 



The external surface of the inferior turbinated bone is concave, ami helps 

 to form the inferior meatus. 



The internal surface of the inferior turbinated bone is convex. 



The extremities of this bone are narrow and pointed. 



The inferior border (free border) passes to within half an inch of the floor 

 of the nose. 



The superior border articulates with the inferior turbinated crest of the 

 superior maxillary bone anteriorly, and with the inferior turbinated crest of 

 the palate bone posteriorly. 



The lachrymal process is on the superior border at the junction of the 

 anterior one-fourth with the posterior three-fourths. It articulates with the 

 inferior angle of the lachrymal bone and also with the nasal process of the 

 superior maxillary bone, thus helping to form the nasal duct. 



The ethmoidal process is on the superior border about half way between 

 the lachrymal process and the posterior extremity of the bone. It articulates 

 with the unciform process of the ethmoid. 



The maxillary process, which is immediately below the ethmoidal process 

 but on the external surface of the bone, articulates with the lower edge of the 

 aperature of the antrum of Eighmore, and also helps to close this opening. 



Ossification.- It ossifies from one center. 



Articulation. — It articulates with four bones. The ethmoid of the 

 cranium, superior maxillary, lachrymal, and palate of the face. 



Attachment of Muscles. — It has no muscles attached to it. 



Bl< m >i> Si pply. — 



Vomer Bone. (Plate CCLXI). 



The vomer (ploughshare) forms the postero-inferior part of the nasal 

 septum and is a single bone. It has the following points for consideration: 



The oaso-palatine grooves or canals are situated on each side of this hone 

 r unnin g downward and forward to the intermaxillary suture. They are for 

 the naso-palatine nerves. 



The posterior border of the vomer is concave and free. Its lower portion 

 is thin, while its upper portion is divided. 





