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The ENTOPTERYGOID is small, and its ventral half lies closely against the inner surface 

 of a part of the cartilage of the apparatus that lies between the metapterygoid and the ectopterygoid, 

 along the dorsal edge of the quadrate. The dorsal half of the bone projects beyond the cartilage, 

 is concave on its outer and convex on its inner surface, and lies against the under surface of and gives 

 insertion to a portion of the adductor arcus palatini. The anterior end of the bone rests in the grooved 

 dorsal edge of the dorsal limb of the ectopterygoid, its posterior end not quite reaching, in small 

 specimens, the anterior end of the metapterygoid. 



The PALATI NE has a body, a maxillary process, and a stout and large ventral flange of derm- 

 al origin. The hind edge of the ventral flange is jagged and suturates with the anterior edge of the 

 dorsal limb of the ectopterygoid. The hind end of the body of the bone is in synchondrosis with the 

 cartilage of the posterior ethmoid process of the apparatus. The maxillary process of the bone curves 

 slightly antero-mesially, is flattened on its dorso-lateral surface, and there rests against and is firmly 

 bound to the internal surface of the dorso-anterior edge of the lachrymal. A small eminence at the 

 base of the maxillary process gives insertion to the rostro-palatine ligament, and immediately posterior 

 to this process there is an obliquely transverse facet which articulates with the anterior palatine 

 process of the ethmoid cartilage. The vomero-palatine ligament is unimportant. The anterior end 

 of the maxillary process of the bone is capped with cartilage and articulates with the dorsal surface 

 of the maxillary, in the angle between the lateral surface of the ascending process and the shank 

 of that bone. The posterior portion of the body of the palatine, and the cartilage that forms the 

 posterior ethmoid process of the apparatus, are firmly bound to the lachrymal, in the manner already 

 described. Between this posterior part of the palatine and the base of its maxillary process, the dorso- 

 lateral surface of the body of the bone is slightly hoUowed, this hollow lodging the lateral half of 

 the nasal sac. 



The palato-c[uadrate, «s a whole, forms a plate which is slightly concave on its ectal surface, 

 and the two anterior infraorbital bones together form a plate which is slightly concave on its ental 

 surface. These two plates are firmly bound to each other by their anterior edges, while by their 

 posterior edges they are firmly bound to the preopercular and hyomandibular. The two plates 

 together thus form a flat, hollow, trapezoidal structure, open both dorso-mesially and ventro-laterally 

 by large and relatively narrow openings. The space enclosed between the two plates is, in the recent 

 State, almost completely fiUed by the adductor mandibulae muscle. 



The HYOMANDIBULAR is cross-shaped, the arm of the cross lying obliquely to the shank. 

 The summit of the longitudinal ridge on the outer surface of the shank projects forward, and so 

 gives to the anterior surface of the bone a grooved appearance. The dorsal portion of this forwardly 

 projecting ridge gives support, on its lateral surface, to the fourth bone of the infraorbital series. 

 The shank of the bone is traversed by a facialis canal, the ventral opening of that canal lying anterior 

 to the longitudinal ridge. From this canal a single brauch canal arises, and running postero-ventrally 

 opens on the outer surface of the bone, near the ventral end of the thin web of bone that fills the 

 Space between the opercular process and the ventral portion of the shank of the bone. It transmits 

 a nerve destined to innervate the two dorsal ones of the latero-sensory organs in the preopercular, 

 a Single canal thus here replacing the two canals found in Scorpaena. A foramen leads directly 

 from the main canal for the facialis onto the anterior surface of the bone, but it only transmits 

 a blood vessel. 



