324 
A. LIAUTARD. 
terior border of the maxillary bone. A part of the deep fibres of the 
muscle, specially those which are in front of the temporo maxillary 
articulation, have a direction transversal to that of the fibres of the 
superficial layer. A beautiful nacreous aponeurosis which looses itself 
at two or three centimetres of the moveable insertion, covers the muscle 
and has its greatest thickness near the maxillary crest. 
We may also mention in the enumerations of these layers the por¬ 
tion of the alveolo labialis* muscle which runs up backward to the 
last molar tooth. This muscle is run on each side by the two molar 
glands, the superior is in connexion with the masseter, the inferior is 
immediately situated between the inferior border of the muscle and the 
mucous membrane of the cheek. 
The skeleton of the region is formed by the inferior maxillary, the 
superior maxillary, the malar bone, and a portion of the temporal. .The 
inferior border of the masseterine region corresponds to the space which 
separates the fourth from the fifth molar. The two lamellae of the in¬ 
ferior maxillary are more or less separated from each other, according 
to the age of the animal. Below the teeth runs the maxillo dental canal, 
where the inferior maxillary and artery of the same name are lodged. 
The opening by which the nerve enters the bone is hollowed in the in¬ 
ternal laminae about 16 centimetres below the condyle of the maxillary. 
The superior maxillary nerve passes above the roots of the superior 
molar and makes its exit by the sub-orbital foramen, as we have said it 
in speaking of the chanfrin. 
Blood-vessels .—Below the condyle of the maxillary, between the 
cutaneous muscle and the masseter, we find the temporal trunk with its 
vein satellite, and the facial nerve. The artery is so superficial that its 
pulsations are easily felt. It divides into two branches—the transversal 
artery of the face, running along the zygomatic crest, and deeping into 
the thickness of the masseter, and the masseterine artery. The maxillo 
muscular artery penetrates also in the masseter muscles, towards the 
middle of its posterior border; it deeps immediately in the fibres of the 
muscle running towards its inferior attachment. 
The veins are satellite of the arteries, but we find, beside, in that 
region, first, the alveolar vein, situated in a deep position, between the 
masseter and the superior maxillary bone, and running along the molar 
gland. This vessel is an enormous canal of communication thrown be¬ 
tween the external maxillary on one side and the cavernous sinus 
^Buccinator of Percival. 
