THE FACE 



325 



border belongs to the sphenoiclal process. The outer border is short 

 and rounded ; it is directed backward and inward, and is continuous 

 with the outer borders of the maxillary process in front and the 

 sphenoidal process behind. In shape the ethmoidal process is oblong ; 

 it lies at the bottom of the orbit, between the maxillary, the lachrymal, 

 the frontal, and the orbitosphenoid. 



Its outer, or orbital, surface is smooth, and slightly concave from 

 above downward. Below and behind the middle is the large, oval, 

 spheno-palatine foramen, for the transmission of the posterior nasal 

 vessels and nerves. A ridge, more or less distinctly marked, runs 

 from this foramen upward and ' backward to the posterior margin, 



With Lachrymal and sometimes 

 <)x Planum of Ethmoid. 



With Orbital Plate of 

 Maxillary. 



With Tuberosity of Maxittary. 



Posterior' Palatine Foramen. 



FIG. 253. 



With Palatine Plate of Maxillary. 

 Iloi'i.imtal Plate. 



With Opposite Palatine. 

 With Orbital Plate of Frontal. 



Spheno-palatine Foramen. 



Vertical Plate. 



With Presphenoid. 

 With Orbitosphenoid. 



With Pteryyoid. 

 LEFT PALATINE BONE, ORBITAL ASPECT. 



whence it is continued on the side of the orbitosphenoid. It marks 

 the upper line of attachment of the external pterygoid muscle. Above 

 this ridge, running in the same direction, but forming an angle with 

 it, is the fissure leading from the foramen to the upper border. 



The inner, or nasal, surface of the ethmoidal process of the vertical 

 plate (Figs. 252, 254) is rough and marked by ridges running down- 

 ward and forward. These ridges are continuous with the ridges on 

 the inner surface of the frontal and orbitosphenoid bones, to which 

 are attached the partitions of the lateral ethmoid. In some specimens 

 these ridges are not distinctly marked ; in well-developed skulls, how- 

 ever, they are three in number, arranged as follows : 



