THE FACE 375 



the nasal cartilage ; it is sometimes notched at the inferior end of the 

 groove on the nasal surface. 



The external border is bevelled at the expense 

 of the anterior surface, and is overlapped by the 

 anterior edge of the nasal process of the maxillary. 



The internal or medial border is prolonged back- 

 ward, forming; a crest to which are attached the nasal 



o 



spine of the frontal and the anterior border of the 



mesethmoid and its cartilage. LEFT NASAL BONE, 



ANTERIOR VIEW. 



The inferior medial angle forms with its fellow l frontal border . 2) 

 on the other nasal a variable nasal spine, or nasal 



THE LACHRYMAL BONES. 



ferior border ; 5, nasal 

 foramen. 



General Description. The Lachrymals are thin bones lying at 

 the inner, lower corners of the orbits (Fig. 294). Each is merely a 

 small plate, about as thin as stiff paper. The shape is usually square, 

 but may vary when encroached upon by the surrounding bones. The 

 lachrymal presents two surfaces and four borders. 



The external or orbital surface (Fig. 295) is gently concave in 

 all directions. Its anterior border is nearly straight, prominent, 

 and everted, and, when the bone is in position, directed upward and 

 slightly backward. Its upper end is prominent, and articulates with 

 the lachrymal tubercle of the maxillary, or itself produces the 

 tubercle ; the entire border articulates with the posterior border of the 

 ascending plate of the maxillary. Its superior or frontal border, 

 which is irregular and serrated, faces backward and upward and joins 

 the anterior part of the lower border of the orbital plate of the frontal. 

 The anterior-superior angle, where the lachrymal meets the maxillary 

 and frontal bones, marks the point on the skull known as the dacryon. 1 

 The os planum of the lateral ethmoid, when uncovered by a deficiency 

 in the surrounding bones, appears above and behind this border, 

 between the lachrymal, frontal, and palatine. The posterior border 

 is straight, faces downward and backward, and articulates with the 

 anterior part of the vertical plate of the palatine. The inferior 

 border is slightly emarginate and rounded ; it faces downward and 

 somewhat forward and joins the crest of the maxillary, which separates 



1 (Gr.) a tear. 



