THE PACE 345 



maxillaries, and behind, on the higher part, the vomer. At the outer 

 part the upper surface rises gradually into the nasal surface of the 

 bone, but behind it is separated from it, in part, by the lower end of 

 the crest for the maxillo-turbinal. A slight longitudinal elevation is 

 noticeable at about the middle of the surface. On the inner side of 

 this elevation a shallow groove leads forward into the anterior palatine 

 foramen ; and on the outer side, further back, a long depression helps 

 to lodge the maxillo-turbinal. The upper surface is covered by the 

 mucous membrane of the nasal chamber. 



The Nasal Process is that part of the bone extending on the outside 

 upward from the end of the upper limit of the infraorbital foramen 

 and on the inside from the line of the lachrymal canal. It is about 

 one-third higher than wide, and is directed slightly backward and 

 decidedly inward as well as upward. It is thin and of nearly uniform 

 thickness throughout. The nasal process has two surfaces and three 

 borders. 



The external surface (Fig. 265) is oblong, with its upper, anterior 

 angle rounded. It is smooth and gently concave in both directions, 

 and faces outward and forward. From its lower posterior part above 

 the infraorbital foramen springs the upper anterior root of the malar 

 process. 



The anterior border is arcuate and sharp, and articulates through- 

 out its lower half with the posterior edge of the ascending process of 

 the premaxillary, and throughout its upper half with the outer margin 

 of the nasal bone. Above this point may be said to begin the promi- 

 nent, rounded, upper end, which fits into a deep notch in the anterior 

 extremity of the frontal bone and is embraced by its nasal process in 

 front and by its internal angular process behind. 



The slightly emarginate posterior border joins, by its lower half, 

 the lachrymal ; its upper half, which is bevelled at the expense of the 

 anterior surface, is overlapped by the external lip of the internal 

 angular process of the frontal. At about the middle of the posterior 

 border, above the point where the frontal and the lachrymal meet 

 behind, there is often a swelling, known as the lachrymal tubercle. 

 The upper posterior angle is prominent. 



The internal surface (Fig. 270) of the nasal process is slightly 

 convex from before backward. It is divided into two parts by a 

 slightly raised curved line which marks the attachment of the cleft 



