110 



SPECIAL ANATOMY OF THE SKELETON 



Tensor palati muscle. At the outer extremity of this ridge is a deep groove, the 

 pterygopalatine groove (sulcus pteryyopalatinus), converted into a canal by its 

 articulation with the tuberosity of the maxilla, and forming the lower end of the 

 posterior palatine canal (canalis pteryyopalatinus). Near this, groove the orifices 

 (foramina palatina minora) of one or two small canals, accessory posterior pala- 

 tine canals (canales palatini) may be seen. Through the posterior palatine canal 

 emerge the descending palatine artery and the great posterior palatine nerve. 



Borders. The anterior is serrated, bevelled at the expense of its inferior sur- 

 face, and articulates with the palatal process of the maxilla. The posterior 

 is concave, free, and serves for the attachment of the soft palate. Its inner 

 extremity is sharp and pointed, and when united with the opposite bone forms a 



Sphenopalatine for. 



Sup. turbinated crest. 



Inf. turbinated crest. 



Sup. turbinated crest. 



Inf. turlinated crest. 



Ant. nasal spine. 



FIG. 78. Internal surface of left maxilla. 



projecting process, the palatine spine (spina nasalis posterior}, for the attachment 

 of the Azygos uvulae muscle. The external is united with the lower part of the 

 perpendicular plate almost at right angles. The internal, the thickest, is serrated 

 for articulation with its fellow of the opposite side; its superior edge is raised into 

 a ridge, which, united with the opposite bone, forms a crest (crista nasalis}, into 

 which the vomer is received. 



The Vertical or Perpendicular Plate (pars perpendicular is} (Figs. 79 and 80) 

 is thin, of an oblong form, and directed upward and a little inward. It presents 

 two surfaces, an external and an internal, and three borders. 



Surfaces. The internal, medial, or nasal surface (fades nasalis) presents at its 

 lower part a broad, shallow depression, which forms part of the inferior meatus 

 of the nose. Immediately above this is a well-marked ridge, the inferior turbin- 

 ated crest (crista conchalis), for articulation with the turbinated bone; above this 

 a second broad, shallow depression, which forms part of the middle meatus, sur- 

 mounted above by a horizontal ridge less prominent than the inferior, the superior 

 turbinated crest (crista ethmoidalis), for articulation with the middle turbinated 

 process. Above the superior turbinated crest is a narrow, horizontal groove,, 

 which forms part of the superior meatus. 



