86 THE SKELETON. 



separation of the facial from the zygomatic surface. In front it is concave, form- 

 ing part of the facial surface ; behind it is also concave, and forms part of the 

 zygomatic fossa ; above it is rough and serrated for articulation with the malar 

 bone ; whilst below a prominent ridge marks the division between the facial and 

 zygomatic surfaces. A small part of the Masseter muscle arises from this process. 

 The Nasal Process is a strong, triangular plate of bone, which projects upward, 

 inward, and backward by the side of the nose, forming part of its lateral boundary. 

 Its external surface is concave, smooth, perforated by numerous foramina, and gives 

 attachment to the Levator labii superioris alseque nasi, the Orbicularis palpe- 

 brarum, and Tendo oculi. Its internal surface forms part of the outer wall of 

 the nasal fossae : at its upper part it presents a rough, uneven surface, which ar- 

 ticulates with the ethmoid bone, closing in the anterior ethmoidal cells ; below this 

 is a transverse ridge, the superior turbinated crest, for articulation with the mid- 

 dle turbinated bone of the ethmoid, bounded below by a shallow smooth concavity 

 which forms part of the middle meatus ; below this again is the inferior turbinated 

 crest (already described), where the process joins the body of the bone. Its upper 

 border articulates with the frontal bone. The anterior border of the nasal process 

 is thin, directed obliquely downward and forward, and presents a serrated edge 

 for articulation with the nasal bone ; its posterior border is thick, and hollowed 

 into a groove, the lachrymal groove, for the nasal duct : of the two margins of this 

 groove, the inner one articulates with the lachrymal bone, the outer one forms 

 part of the circumference of the orbit. Just where the latter joins the orbital 

 surface is a small tubercle, the lachrymal tubercle ; this serves as a guide to the 

 position of the lachrymal sac in the operation for fistula lachrymalis. The 

 lachrymal groove in the articulated skull is converted into a canal by the lachrymal 

 bone and lachrymal process of the inferior turbinated ; it is directed downward, 

 and a little backward and outward, is about the diameter of a goose-quill, slightly 



Anterior palatine canal. 



Foramina of Stenson. 



Foramen of Scarpa. 



ior palatine canal. 



Accessory palatine foramina. 



FIG. 51. The palate and alveolar arch. 



narrower in the middle than at either extremity, and terminates below in the 

 inferior meatus. It lodges the nasal duct. 



The Alveolar Process is the thickest and most spongy part of the bone, broader 

 behind than in front, and excavated into deep cavities for the reception of the teeth. 



