THE PALATINE BONE 



167 



process, which is directed backward and lateralward from the junction of the two 

 parts, and the orbital and sphenoidal processes, which surmount the vertical 

 part, and are separated by a deep notch, the sphenopalatine notch. 



The Horizontal Part (pars horizontal; horizontal plate) (Figs. 168, 169). The 

 horizontal part is quadrilateral, and has two surfaces and four borders. 



Surfaces. The superior surface, concave from side to side, forms the back part 

 of the floor of the nasal cavity. The inferior surface, slightly concave and rough, 

 forms, with the corresponding surface of the opposite bone, the posterior fourth 

 of the hard palate. Near its posterior margin may be seen a more or less marked 

 transverse ridge for the attachment of part of the aponeurosis of the Tensor veli 

 palatini. 



Maxillary surface 



Superior meatus 

 Sphenopalatine foramen 



Maxillary 

 process 



Sphenopalatine 

 foramen 



Sphenoidal process 

 Articular poi-tion 



Non-articular 

 portion 



Posterior 

 _ nasal 

 Mwsculus uvulce spine 



HORIZONTAL PART 



FIG. 168. Left palatine bone. 

 Enlarged. 



Pyramidal 

 process 



HORIZONTAL 

 PART 



Nasal aspect. 



Fid. 169.- 



-Left palatine bone. 

 Enlarged. 



Posterior aspect. 





Borders. The anterior border is serrated, and articulates with the palatine process 

 f the maxilla. The posterior border is concave, free, and serves for the attachment 

 >f the soft palate. Its medial end is sharp and pointed, and, when united with 

 hat of the opposite bone, forms a projecting process, the posterior nasal spine 

 or the attachment of the Musculus uvulae. The lateral border is united with 

 the lower margin of the perpendicular part, and is grooved by the lower end of 

 the pterygopalatine canal. The medial border, the thickest, is serrated for articu- 

 lation with its fellow of the opposite side; its superior edge is raised into a ridge, 

 which, united with the ridge of the opposite bone, forms the nasal crest for articu- 

 lation with the posterior part of the lower edge of the vomer. 



The Vertical Part (pars perpendicularis; perpendicular plate) (Figs. 168, 169). 

 The vertical part is thin, of an oblong form, and presents two surfaces and four 

 borders. 



Surfaces. The nasal surface exhibits at its lower part a broad, shallow depres- 

 sion, which forms part of the inferior meatus of the nose. Immediately above this 

 is a well-marked horizontal ridge, the conchal crest, for articulation with the 

 inferior nasal concha; still higher is a second broad, shallow depression, which 

 forms part of the middle meatus, and is limited above by a horizontal crest less 

 prominent than the inferior, the ethmoidal crest, for articulation with the middle 

 nasal concha. Above the ethmoidal crest is a narrow, horizontal groove, which 

 forms part of the superior meatus. 



