Nos. IAND2.] ANATOMY OF SCOMBER SCOMBER. 193 



The middle tendon of A^ arises from the upper, superior 

 maxillary tendon of the muscle, at its base. It runs downward 

 and forward, internal to the posterior tendon of A-^, and internal 

 to the hind end of A^. There it joins, in part, a fascia on the 

 inner surface of A^, and in part it continues downward and for- 

 ward along the lateral surface of that fascia, between it and the 

 muscle fibers of A^, toward the ventral edge of the latter muscle. 

 Slightly dorsal to that ventral edge it pierces A^, reaches its 

 lateral surface and is there inserted on the mesial surface of the 

 articular, ventral to ^leckel's cartilage. 



The lower, posterior tendon of A^ (t. a, art) runs downward 

 and forward along the lateral surface of A^ to the hind end of 

 Meckel's cartilage, where it is inserted partly on that cartilage 

 and partly on the mesial surface of the articular immediately 

 above the hind end of the cartilage, a slight eminence on the bone 

 marking its place of insertion. From Aleckel's cartilage, im- 

 mediately in front of the insertion of this tendon, there is a tuft 

 of tendinous fibers which run upward and backward parallel to 

 the tendon of A^, into A^, and there disappear. 



A2 is a strong muscle forming much the larger part of A^A^ 

 On its mesial surface, at its distal end, a tendon forms and sepa- 

 rates distally into two parts. One of these parts is joined by 

 a part of the middle tendon of A^, and by the posterior and deeper 

 tendon of A^, to form with those tendons the tendon that was 

 above referred to as tendon A.A^, which tendon then joins the 

 fascia on the mesial surface of A^. The other part of the tendon 

 of A^ becomes a short strong tendon which runs downward and 

 forward into, and sometimes along the outer surface oi A^, and 

 gives origin to part of the fibers of that mviscle. Most of the 

 muscle fibers of A^ are inserted on these two tendons; some of 

 them, however, pass directly into and become part of the man- 

 dibular muscle A^. 



A^, the mandibular part of the adductor, is a thin, broad mus- 

 cle lying internal to and covering almost the entire inner surface 

 of the mandible. Its mesial surface, excepting only its ventro- 

 posterior corner, is covered by a tendinous fascia, the mesial 

 surface of which, as there is no splenial in Scomber, lies directly 

 against the lining membrane of the mouth cavity. From the 



