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The postorbital process of the skull is a short broad pyramidal process wbich lies at the anterior 

 two-fifths, approximately, of the length of the brain case, and in the dorsal two-fifths only 

 of the lateral surface of the skull. The process, as always, separates the orbital and lateral surfaces 

 of the brain case, but these two surfaces here lie in nearly the same plane, the postorbital process 

 forming simply a large ridge and not a marked angle between them, as it does in Scorpaena. Because 

 of the Position of the orbital surface of the brain case, so slightly inclined to its lateral surface, and 

 because, also, of the absence of a basisphenoid, the orbital opening of the brain case is very large. 

 The postorbital corner of the frontal lies in the transverse plane of the lateral bounding edges of the 

 orbital opening of the brain case, considerably anterior to the postorbital process of the skull. 



The postorbital process is formed, as usual, by portions of the proötic and sphenotic bones, 

 and it bears a large circular facet for the anterior head of the hyomandibular. Starting from the 

 base of the process, an angular edge runs antero-laterally toward the antero-ventral corner of the 

 brain case, another but much more rounded edge running postero-ventrally toward the hind end of 

 the brain case. Between these two edges and the base of the skull there is a flat smooth and raised 

 portion of the lateral surface of the brain case, the flat bulla acustica forming the rounded dorso- 

 posterior edge of the surface. 



Anterior to this flat surface and to the postorbital process, there is a depressed region which 

 forms the orbital surface of the brain case. Dorso-posterior to the flat surface there is, on the lateral 

 surface of the brain case, a large triangulär subtemporal depression, sinailar to but more extensive 

 than the one in Scorpaena, the depression here reaching almost to the dorsal edge of the lateral sur- 

 face of the skull. Anterior to this subtemporal depression, between it and the postorbital process, 

 there is a shallow groove, which apparently represents the fossa there found in Scorpaena. In the 

 postero-ventral corner of the subtemporal depression is the vagus foramen, the glossopharyngeus 

 f oramen lying slightly anterior to it at the ventral edge of the depression ; both foramina perf orating 

 the exoccipital. The anterior corner of the subtemporal depression is shut off from the orbital surface 

 of the brain case by the base of the postorbital process, and does not, as in Scorpaena, connect, by 

 a groove, with the facialis opening of a trigemino-facialis chamber. Dorsal, or dorso-anterior to the 

 dorsal corner of the subtemporal depression is the small oval facet for the posterior articular head 

 of the hyomandibular, this facet lying wholly on the pterotic. 



The DILATATOR FOSSA is small, lies directly anterior to the posterior articular facet 

 for the hyomandibular, and almost directly dorsal to the anterior articular facet for that bone. 

 The fossa lies partly in the sphenotic and partly in the pterotic, and is roofed by the pterotic alone, 

 the postfrontal here lying wholly anterior to it. 



The TEMPORAL FOSSA is small, and five of the six fossae in my three specimens open 

 mainly on the lateral surface of the skull, between the opisthotic leg of the suprascapular and 

 the posterior process of the pterotic. The usual opening, on the posterior surface of the skull, be- 

 tween the opisthotic leg of the suprascapular and the epiotic, is, in four of these five instances, reduced 

 to a small opening, and in one instance almost entirely closed. 



This reduction of this opening is due to the encroaching ingrowth of both the epiotic and 

 the opisthotic leg of the suprascapular, but mainly to the marked broadening of the latter leg. When 

 the suprascapular is removed the hind end of the fossa is found to be fairly large, and to lie at the 

 extreme dorso-lateral corner of the hind end of the skull. The fossa, thus exposed, seems short when 



