ADAMS: SKULL OF THE WOLF-EEL. 349 



Articulations. 



It articulates dorsally with the hyomandibular. The lower 

 two-thirds is sheathed in the quadrate and the dorsal one-third 

 articulates with metapterygoid. Posteriorly it articulates with 

 the quadrate on the lower third of the posterior edge, the other 

 one-third being free. 



Quadrate. (Plate XXV, Quad.; plate XXXV, figs. 57, 58.) 



The quadrate is a peculiarly shaped bone, occupying the 

 angle of the suspensorium. The posterior part of the bone is 

 heavy and the anterior part is thin and fan-shaped. There is 

 a notch on the inner side where the symplectic is sheathed. 



The outer face is rod-like at the posterior part, and the an- 

 terior part is thin. Anterior to the rod-like posterior end the 

 face is pushed inwardly so that the fan-shaped portion is 

 farther in than the heavy part at the posterior. The face is 

 marked with small ridges and numerous foramina. All con- 

 verge at the posterior ventral angle. The inner face of the 

 bone is striated and has numerous ridges like the outer face. 

 On the anterior edge there is a depression, dropped below the 

 rest of the face and forming an articulation. This depression 

 occupies about one-third of the face. It narrows down ven- 

 trally and furnishes a good articulation for the pterygoid. 

 The ventral posterior angle is pushed in, forming an articula- 

 tion with the mandible. 



The posterior part of the quadrate is very heavy and solid. 

 It is smaller dorsally, swelling out a little below the median 

 line, then narrowing again, forming a constriction above the 

 lower ventral part, which is the heaviest part of the bone. The 

 posterior face of this part is deeply grooved, the groove fitting 

 over the preopercular. The deep notch between the rod and the 

 fan-shaped part is cut out at the expense of the inner face, 

 only half of the notch showing from the outer view of the 

 quadrate. 



The articulation for the mandible is in two parts, divided by 

 a constriction. This articulating surface points slightly an- 

 teriorly. The larger part of the articulation is at the ventral 

 part of the rod. The lower part is expanded and makes a large 

 convex surface. 



