8 THE SESAMOID ARTICULAR 



Dr. Allis that part of it that posteriorly runs internal to the levator arcus 

 palatini may represent A-3 and the part external to it A-2. 



Dentex vulgaris. 



The superior part of the adductor mandibulae muscle consists of 

 two parts : ( i ) A dorsal muscle which at first sight appears to be made 

 up of two muscles an outer and an inner one. The outer part is strongly 

 attached to the maxillary at one end by a short stout tendon, and to the 

 preopercular ridge at the other end by a longer, but scarcely less stout, 

 tendon. Above the preopercular tendon projects the inner part. It 

 originates on the preopercle and runs downward and forward obliquely 

 behind the outer part, and is attached anteriorly to the lower edge of the 

 outer part, and to a thick sheet of tendon that covers the greater part 



L<vp. 



At 



Fig. 2. DENTEX VULGARIS 

 A 1-2-3, muscles of Vetter; Lap, levator arcus palatini. 



of the inner surface of all of the muscles. The lower edges of the inner 

 and the outer parts are continuous, so that when the two are spread 

 out it is apparent that they are a single muscle folded upon itself. It 

 represents A-i of Vetter. 



(2) A ventral muscle, which is larger than the dorsal muscle, origi- 

 nates on the preopercular ridge and the surface of the anterior adjoining 

 bones. The thick sheet of tendon, that covers much of the inner part of 

 this and the dorsal muscle, shallowly invades this muscle at about its 

 middle, and along the plane of this invasion the muscle may be rather 



