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The rod-like SYMPLECTIC lies in the symplectic groove on the internal surface of the quad- 

 rate. Between it, and the preopercular and the posterior process of the quadrate there is a large 

 oval opening which transmits the mandibularis externus facialis and the arteria hyoidea. Anterior 

 to the symplectic, between it and the quadrate, there is a small canal which transmits the mandi- 

 bularis internus facialis. 



The arteria hyoidea has a course exactly similar to that in the fishes already described. 



The PREOPERCULAR has slightly indicated dorsal and ventral limbs, separated by a low 

 and granulated ridge on the outer surface of the bone. This granulated ridge is much more apparent 

 in small than in large specimens, and terminates posteriorly in a spine which, in small specimens, is 

 sharply pointed. Immediately ventral to this spine there is, in these small specimens, a smaller spine. 

 The dorsal limb of the bone is firmly bound to the hyomandibular, the ventral limb being similarly 

 bound to the posterior process of the quadrate. The anterior edge of the bone gives support and is 

 bound to the hind edge of the second bone of the infraorbital series. The bone is traversed its füll 

 length by the preopercular latero-sensory canal, and lodges six Organs of the line, the second organ 

 from the dorsal end of the bone being a double one in the one specimen examined. 



The OPE RCULAR has a large bluntly pointed process which rises from the dorsal edge of the bone 

 immediately dorsal to the articular facet for the hyomandibular, and, projecting dorsally or dorso- 

 anteriorly, nearly reaches the dorso-lateral edge of the skull in the suprascapular region. The inner 

 surface of the process is slightly concave and gives Insertion to the adductor operculi, that muscle 

 having a large surface of origin in the subtemporal depression on the lateral surface of the skull, the 

 surface of origin of this muscle lying immediately posterior to that of the adductor hyomandibularis. 

 Immediately posterior to the base of the process, on the inner surface of the dorsal edge of the oper- 

 cular, the levator operculi has its Insertion; this muscle arising from the dorsal margin of the lateral 

 surface of the pterotic in a line beginning immediately posterior to the latero-sensory tube that 

 anastomoses with the dorsal end of the preopercular canal. The dilatator operculi arises partly in 

 the dilatator fossa and partly on the external surface of the dorsal end of the hyomandibular, and is 

 inserted on the anterior edge of the articular facet for the hyomandibular. On the hind edge of the 

 opercular there are two stout spines, the dorsal one curving upward so that its point is directed almost 

 dorsally. 



The SUBOPE RCUL A R is a long, thin and delicate bone. In one of my large specimens the ventral 

 half of this bone was wanting, and the dorsal half was almost completely ankylosed with the hind 

 edge of the opercular. 



The INTEROPERCULAR is bound by strong ligamentous tissue, at about the middle of its 

 dorso-anterior edge, to the interhyal and ceratohyal. Its antero-ventral end is bound, by a short 

 strong ligament, to the hind end of the mandible. 



The MANDIBLE is relatively longer and more slender than that of Scorpaena. The hind 

 edge of the dentary is V-shaped and receives, in the angle of the V, the long pointed anterior end of 

 the articular, overlapping that bone externally. The dorsal arm of the V reaches the summit of the 

 coronoid process of the articular, and is bound to its internal surface, slightly below the summit 

 of the process. Between this arm of the dentary and the adjoining parts of the articular there is a 

 relatively small and narrow space. The dorsal edge of the dentary is broad and is covered with small 

 villiform teeth; and immediately ventral to this toothed surface there is a deep longitudinal groove 



