MASSETER MUSCLE. 87 



other muscular branches enter the nmsseter. Some anterior auricular 

 offsets are distributed to the pinna and meatus of the external ear. 



b. The transverse facial branch quits the temporal artery opposite the 

 condyle of the jaw, and is directed forwards over the masse ter muscle 

 (p. 41) ; on the side of the face it supplies the muscles and integuments, 

 and anastomoses with the facial artery. 



c. The middle temporal branch arises just above the zygoma, and pierces 

 the temporal aponeurosis to enter the substance of the temporal muscle : it 

 anastomoses with branches of the internal maxillary artery. 



d. A small branch of the temporal artery is likewise found between the 

 layers of the temporal fascia ; this anastomoses with an offset of the lachry- 

 mal. 



The temporal vein commences on the side of the head (p. 21) and is con- 

 tiguous to its companion artery. Near the zygoma it is joined by the 

 middle temporal vein ; next it receives branches which are companions of 

 the offsets of the artery ; arid it ends by uniting with the internal maxil- 

 lary vein. 



Directions. The lower part of the neck will not be used again for some 

 days, so that the dissector may stitch together the flaps of skin, when he 

 has applied salt to preserve it. 



SECTION VI. 



PTERYGO-MAXILLARY REGION, 



IN this region are included the muscles superficial to and beneath the 

 ramus of the lower jaw, together with the articulation of that bone. In 

 contact with the muscles (pterygoid) beneath the jaw, are the internal 

 maxillary bloodvessels, and the inferior maxillary trunk of the fifth nerve. 



Dissection. The masseter muscle, which is superficial to the bones, has 

 been partly laid bare in the dissection of the facial nerve. To see it more 

 fully the branches of the facial nerve, and the transverse facial artery should 

 be cut through, and turned backwards off the face. A little cleaning will 

 suffice to define the origin and insertion of the muscle. 



Should there be any tow or cotton wool in the mouth let it be removed. 



The MASSETEK (fig. 6, 10 ) is partly aponeurotic at the upper attachment. 

 It arises from all the lower border of the zygomatic arch, extending for- 

 wards to the upper jaw ; and from the inner surface of the arch by fine 

 fleshy fibres. Most of the fibres are inclined down and somewhat back, 

 and are inserted into the outer surface of the coronoid process, ramus, and 

 angle of the lower jaw ; but a few are fixed into the contiguous part of 

 the body of the bone as far as the second molar tooth. Some of the 

 hinder and deeper fibres are inclined downwards and forwards across the 

 others^ 



The lower part of the masseter is subcutaneous, but the upper is partly 

 concealed by the parotid gland (socia parotidis), and is crossed by Sten- 

 son's duct, and by the transverse facial vessels and the facial nerve. The 

 anterior border projects over the buccinator muscle, and a quantity of fat 

 resembling that in the orbit is found beneath it. The muscle covers the 



