284 



MAMMALIAN ANATOMY 



below, the anterior cerebral fossa, or a third of the cranial cavity. It 

 is marked by several wide, shallow grooves running downward and 

 forward, which contain convolutions of the anterior cerebral lobe of 

 the brain. 



Near its anterior border as it curves to the median plate above is 

 a very small venous foramen. Its lower border, which is directed out- 

 ward and backward, is serrated, and articulates with the orbitosphenoid. 

 The posterior border is convex, and joins the parietal above and the 



Posterior part of Frontal Sinus. 



FIG. 207. 



Farjittal Suture. 

 I 



Median Plate of Frontal. 

 Orbital Plate of Frontal. 



Orbital Ridge. 



Opening into Anterior part of Frontal 

 Shuts, with Posterior end of Lat- 

 eral Ethmoid. 



Foramina for Olfactory Filaments. 



Cut Edge of Cribriform Plate. 



Cribriform Plate of 

 Ethmoid. 



Mesethmoid. 



Sinus. 



Vertical Plate of Pala- 

 tine. 



Lachrymal Canal. 



Foramen, ha >; 



a 9. a 



//.('' 

 mm Zygoma. 



IKX*\ 



Malar. 



Maxillary. ^\ ^ 



V^ 



Tuberosity. InfraorWtal 



TRANSVERSE VERTICAL SECTION OF SKULL THROUGH ORBITS, SEEN FROM BEHIND. 



alisphenoid lower down. Near the lower posterior angle the surface 

 presents faint grooves which proceed upward more or less parallel with 

 the posterior border and lodge the anterior meningeal artery. Along 

 the straight superior border is a faint groove for the longitudinal 

 sinus. 



The general shape of the inner surface of the median plate is that 

 of a razor-blade. It is flat, and roughened, especially behind, for ar- 

 ticulation with the opposite bone. A crescentic depressed area in front 

 marks the point of articulation with the nasal bone. It is bounded 



