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with the premaxillary. Each ligament is inserted, as in Scorpaena, on the base of the maxillary 

 process of the palatine. In one of four specimens examined, there was, in the middle line, between 

 the two ligaments, a small disk of bone on which the ligaments had their origins; and it would seem 

 as if this bone might be the rostral bone of Sagemehl's descriptions, a bone which that author con- 

 sidered as an ossification of the rostral cartilage. 



The FRONTAL has a ventral flange, but it is but slightly developed. The anterior end of 

 the bone overlaps externally the bounding edges of the mesethmoid and ectethmoid, those bones 

 separating the frontal, by a considerable interval, from the hind end of the nasal. Mesially the frontal 

 suturates, in the mid-dorsal line, with its fellow of the opposite side. Its hind edge is relatively straight, 

 forms a right angle with its mesial edge, and, extending from the middle line of the head to the mesial 

 edge of the pterotic, suturates its füll length with the anterior edge of the parieto-extrascapular. The 

 posterior portion of the short postorbital portion of the lateral edge of the bone suturates with the 

 pterotic, its anterior portion touching a corner of the postfrontal and also abutting against a raised 

 portion of the sphenotic that comes to the level of the dorsal surface of the skull and has surface 

 markings similar to those of the dermal bones. This little raised portion of the sphenotic forms the 

 dorso-lateral corner of the postorbital process of the skull, and between its hiud edge and the lateral 

 portion of the anterior edge of the pterotic there is a little notch which is occupied by the small post- 

 i'rontal bone. The postero-mesial corner of the raised portion of the sphenotic arches toward and, 

 in medium-sized specimens, touches, or almost touches, the anterior corner of the dermal portion 

 of the pterotic, a circular passage being left between the two bones, which transmits that primary 

 tube of the supraorbital latero-sensory canal that anastomoses with the main infraorbital canal as 

 that canal passes from the postfrontal into the pterotic. The frontal is traversed by the supraorbital 

 latero-sensory canal and lodges five sense organs of that line, the fourth and fifth organs of the line 

 lying relatively close together, without intervening primary tube, as in Scorpaena. 



The PARIETO-EXTRASCAPULAR is a flat bone, and is traversed, near its hind edge, by 

 the supratemporal latero-sensory canal, that canal uniting with its fellow in the mid-dorsal line to 

 form a complete cross-commissure. The bone suturates, in the mid-dorsal line, with its fellow of the 

 ojiposite side, completely covering the supraoccipital excepting only a narrow hind edge of that 

 bone, and, slightly anterior to that edge, a small, variable and irregulär median portion of the dorsal 

 limb of the bone. Anteriorly the bone suturates with the frontal. Laterally it suturates with the 

 pterotic, lateral extrascapular and suprascapular, not appreciably overlapping, in most of my spec- 

 imens, the epiotic process of the latter bone. On its dorsal surface, near the middle of the bone^ 

 there is, in my medium-sized specimens, a slightly raised and granulated ridge, longitudinal in 

 Position, which apparently corresponds to the ridge that forms the lateral boundary of the sub- 

 quadrangular groove on the Vertex of Scorpaena. The section of the supratemporal latero-sensory 

 commissure that is enclosed in the bone lodges one sense organ of that canal. 



The POSTFRONTAL is a small bone that lies in the angular interval between the pterotic 

 and the raised, dermal-like portion of the sphenotic. Its mesial corner approaches closely, or even 

 touches, between those two bones, the lateral edge of the frontal. It is traversed by the infraorbital 

 latero-sensory canal and lodges one organ of that line, innervated by a brauch of the oticus lateralis. 



The LATERAL EXTRASCAPULAR is a small subcircular bone that lies in the space between 

 the pterotic, parieto-extrascapular and suprascapular bones, with all of which bones it is firmly 



