10 



Bones of the Cranium. 



8. Frontal Bone, Os frontis, from behind. 



Frontal portion. The inner surface: is divided by the frontal crest, 

 ( 'rt'xta frontaliSj into 2 halves 5 on both sides are Pacchionian depressio n s. 

 The border of the frontal portion, ^Fa^<|<> coroncdis, commences behind the 

 zygomatic process with a triangular, serrated surface. 



The two orbital portions are separated from each other by 

 the ethmoid;)! notch, Tuc^nrn etlimoidaUs ; on the inferior surface close to the 

 zygomatic process is the lachrymal fossa, Foi-ea ylandulae lacrymalis ; toward 

 the nasal portion a depression, Foi'c-ola troclilearix, sometimes the ITamulus 

 trocldearis (for the pulley of the superior oblique muscle of the eye). 

 The inner border is broad and cellular, the compartments leading to the 

 frontal sinuses, Sinus frontcdes ; between the outer edge of the inner border 

 and the contiguous Ldiiiina papi/racea of the ethmoid bone are the anterior 

 and posterior ethmoidal foramina, Foramen ctlunoidale antcrius ct For. ctlun. 

 poxtcrius; the latter sometimes formed only by the frontal bone. On the nasal 

 portion behind the superior nasal spine is the Foramen coccuui (for a vein); 

 above it the Incixurci Hascilix. 



The frontal bone articulates with 1*2 bones; with the 2 parietal, the 

 sphenoid, the ethmoid bones; with the 2 nasal, the 2 superior maxillary, the 

 2 lachrymal and the 2 malar bones. 



