NORMA FRONTALIS OF THE SKULL. 147 
margin of the outer wall is stout and formed by the malar bone, behind which, 
formed in part by the orbital process of the malar bone and the malar edge (margo 
zygomaticus) of the great wing of the sphenoid, it forms a fairly thick partition 
between the orbit in front and the temporal fossa behind. Crossing this surface 
from above downwards close to the anterior extremity of the spheno-maxillary 
fissure is the suture between the malar bone and the great wing of the sphenoid 
(sutura spheno-zygomatica). This wall is pierced in front by one or two 
small canals (foramen zygomatico-orbitale), which traverse the malar bone and 
allow of the transmission of the temporal and malar branches of the orbital portion 
of the superior maxillary division of the fifth nerve. 
The inner wall of the orbit is formed from before backwards by a small part of 
the frontal process of the superior maxilla, by the lachrymal, and by the os planum or 
orbital plate of the ethmoid (lamina papyracea ossis ethmoidalis), posterior to which 
is a small part of the lateral aspect of the body of the sphenoid in front of the 
optic foramen. Above, the orbital plate of the frontal bone forms a continuous 
suture from before backwards with the bones just enumerated; whilst below, the 
lachrymal and the orbital plate of the ethmoid articulate with the orbital plate of 
the superior maxilla; posteriorly the hinder extremity of the os planum and the 
fore part of the body of the sphenoid articulate with the orbital process of the 
palate. The orbital surface of the lachrymal bone is divided into two by a vertical 
ridge—the lachrymal crest (crista lachrymalis posterior)—which forms in front the 
posterior half of a hollow, the lachrymal groove (sulcus lachrymalis), the anterior 
part of which is completed by the channelled posterior border of the frontal process 
of the superior maxilla. In the lachrymal groove or fossa (fossa sacci lachrymalis) 
is lodged the lachrymal sac, whilst passing from it and occupying the canal, of 
which the upper opening is at present seen, is the membranous nasal duct. The 
extremely thin wall of the lower part of the lachrymal fossa separates the orbit 
from the fore part of the middle meatus of the nasal fossa. To the inner side of 
the upper and fore part of the lachrymal bone, and separated from the orbit merely 
by the thickness of that bone, is the passage leading from the nose to the frontal 
sinus (infundibulum ethmoidale), whilst the part of the bone behind the lachrymal 
erest forms the thin partition between the orbit and the anterior ethmoidal cells. 
Behind, where the body of the sphenoid forms part of the inner wall of the orbit, 
the sphenoidal air sinus is in relation to the apex of that space, though here the 
partition wall between the two cavities is much thicker. 
The skeleton of the face on its anterior surface is formed by the two superior 
maxille, the frontal processes of which have been already seen to pass up to articu- 
late with the internal angular processes of the frontal bone, thus forming the lower 
halves of the inner margins of the orbit. Joined to the upper jaws externally are the 
malar or cheek bones (ossa zygomatica), which are supported by their union with the 
temporal bones posteriorly through the medium of the zygomatic arches. The 
suture which separates the malar from the superior maxilla (sutura zygomatico- 
maxillaris) commences above about the centre of the lower orbital margin and 
passes obliquely downward and outward, its lower end lying in vertical line with 
the outer orbital margin. The two superior maxille are separated by the nasal 
 fossee, which here open anteriorly. Above, the two nasal bones are wedged in 
| between the frontal processes of the maxille ; whilst below the nasal aperture, the 
maxillee themselves are united in the middle line by the intermaxillary suture 
(sutura intermaxillaris). 
The nasal aperture (apertura pyriformis), which les below and in part between 
the orbits, is of variable shape and size—usually pyriform, it tends to be long and 
narrow in Europeans, as contrasted with the shorter and wider form met with in 
the negroid races. Its edges are formed below and on either side by the free 
curved margin of the body and the frontal process of the superior maxilla; and 
above, and partly at the sides, by the free border of the nasal bones. In the 
middle line, inferiorly, corresponding to the upper end of the intermaxillary 
suture there is an outstanding process—the anterior nasal spine (spina nasalis 
anterior) formed by the coalescence of spicules from both maxille; arising from 
this, and passing backwards and upwards, is a thin bony partition—the osseous 
