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One further conditioii of the (Jadoid skull needs to be mcntioncd. The hypophysial fenestra 

 is continued posteriorly, along the ventral surface of the interproötic cartilage, by a relatively deep 

 groove which is prolonged posteriorly by two short recesses in the anterior end of the basioccipital, 

 the two recesses being separated by a thin, vertical, median wall of bone. Laterally, on either side, 

 this groove is in wide communication with a large and deep recess in the proötic. This recess extends 

 antero-dorsally in the bone, lying imraediately mesial to the saccular groove and tapering toward 

 its dorso-anterior end, which end lies slightly postero-mesial to the trigemino-facialis incisure. The 

 bone that forms the outer wall of the recess is thin, and seems to be of purely perichondrial origin. 

 In the specimens of Gadus merLangus that were particularly examined in this connection, and which 

 were all fresh specimens that had been slightly boiled, this recess was filled with loose and apparently 

 fatty tissue: but in the skull that I have of Gadus morrhua, which had not been boiled, the recess 

 lodged the spreading lateral portions of a membrane that covered the ventral surfaces of the proötics 

 and the interproötic cartilage, lying between those structures and the underlying parasphenoid. The 

 recess is certainly the homologue of the proötic vacuity found in the proötic of the 45 mm Scorpaena, 

 as stated when describing that fish. 



In Uranoscopus scaber the interorbital wall is thick, and is deeply and widely excavated, on 

 its dorso-anterior edge, by the large rostral depression. The central portion of the floor of this 

 depression is formed by the subcircular mesethmoid, the ventral surface of which bone rests directly 

 upon the underlving parasphenoid and, perhaps, also on the vomer; but the existence of this latter 

 contact was not established. The anterior portions of the side walls of the depression are formed 

 by the deeply excavated ectethmoids, the posterior halves of the same walls, and the hind wall, 

 being formed bv a specially developed flange of the frontal of either side. No alisphenoid is evident 

 as a separate bone, but it would seem to be represented in, or at least to be replaced by, what appears 

 as an anterior process of the sphenotic. With a ventral process of this alisphenoid part of the 

 sphenotic, and also with an adjoining portion of the anterior edge of the proötic, the ascending process 

 of the parasphenoid is in contact. Posterior to this ventral process, the truncus maxillo-mandibularis 

 trigemini, iindoubtedly accompanied by the buccalis lateralis, issues through a perforation of the 

 side wall of a well-developed trigemino-facialis Chamber. The ramus ophthalmicus superficialis 

 issues from the same chamber through a foramen that lies between the suturating edges of the 

 parasphenoid and the ventral process of the alisphenoid portion of the sphenotic. This ventral process 

 is, accordingly, a well developed parasphenoid leg of the alisphenoid process of the sphenotic. 



Between the parasphenoid leg of the alisphenoid process and the body of that process, dorsally, 

 the parasphenoid posteriorly and ventrally, and the rostral flange of the frontal and the cartilage 

 covering the ventral part of that flange, anteriorly, there is a large subcircular opening. This opening 

 gives exit to the olfactorius, opticus, oculomotorius and trochlearis nerves, and gives entrance to 

 certain of the muscles of the eye, how many or which of them was not deterrained. The opening 

 is accordingly, in function, an olfactorio-opticus fenestra and an orbital opening of the myodome 

 combined. On the internal surface of the proötic, at a certain distance posterior to the hind edge 

 of this opening, there is a low transverse and nearly vertical flange which suturates in the middle 

 line with its fellow of the opposite side. That part of the cranial cavity of the prepared skull that 

 lies anterior to this transverse vertical flange forms a recess in the cranial floor, but belongs properly 

 to the orbit and not to the cranial cavity. The canal for the internal carotid passes inward between 

 the proötic and the hind edge of the ascending process of the parasphenoid, and opens on the floor 



