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dorsal surfaces of those two bones. The process may accordingly be called the lachrymo-palatine 

 process of the bone. From its postero-lateral edge, on the internal surface of the body of the bone, 

 a tall sharp ridge begins, and running postero-mesially, nearly to the hind end of the bone, marks the 

 boundary between the dorsal portions of the rostral Chamber and the nasal pit; those two Chambers 

 being confluent beneath the ridge. Between the hind ends of the ridges of opposite sides there is, 

 on the internal surface of the bone, a deep median pit which nearly perforates the bone and lodges 

 the distal ends of the ascending processes of the premaxillaries. Immediately postero-lateral to the 

 lachrymo-palatine process, close to the narrow space that leads into the nasal opening, the supra- 

 orbital latero-sensory canal begins. and running at first dorso-mesially and then curving posteriorlv, 

 traverses the bone and issues at its hind edge, there entering the frontal. This median so-called 

 ethmoid or prosethmoid bone of Dactylopterus is thus certainly a bone formed by the fusion, in the 

 median line, of the two nasal bones of the fish. 



The ROSTRAL is a narrow, flat and tall cartilage, which lies between the hind ends of the 

 articular processes of the premaxillaries, and gives support, on its dorsal edge, to the ascending 

 processes of those same bones. Its ventral edge has a slight median groove, and this groove slides 

 upon a slight median ridge on the cartilaginous floor of the rostral Chamber. The rostral is relatively 

 small, as are also the maxillary and premaxillary bones; and all of these elements of the upper jaw 

 of the fish are entirely concealed, in dorsal and lateral views, beneath the nasal and lachrymal bones. 



The PREMAXILLARY has a long, flat and pointed ascending process, a relatively long, 

 large and flat articular process, and a short and flat horizontal portion, or body. The short body 

 of the bone ends in a broad blunt end, and its flat oral surface is garnished its füll length, or very 

 nearly so, with small villiform teeth. The ascending process arises by a broad base from the mesial 

 (proximal) end of the body of the bone, and, in the medium-sized specimens, is directed dorsally 

 and but slightly backward. It lies in a nearly longitudinal plane, inclining and but slightly ventro- 

 mesially, the flat surfaces of the processes of opposite sides enclosing between them a deep and 

 narrow groove. The long flat articular process also lies in a nearly longitudinal plane, inclined at a 

 slight angle to the ascending process, the two processes projecting dorso-posteriorly nearly parallel 

 to each other and separated by a narrow intervening space. From the distal surface of the base 

 of the ascending process a rod of tough gristly tissue arises, and extending distally along the dorsal 

 surface of the body of the bone, is attached, at its distal end, to the distal end of the maxillary. 

 This rod of gristly tissue lies in the upper labial, or maxillary dermal fold, thus occupying a position 

 that corresponds to that occupied by a considerable part of the body of the premaxillary in the other 

 fishes of the group, the actual body of the premaxillary of Dactylopterus corresponding, not to 

 the premaxillaries of the other mail-cheeked fishes, but. approximately, to the premaxillaries of 

 * those fishes in which the maxillary is said by Sagemehl to lie lateral (distal) to the premaxillary. 



The MAXILLARY has a relatively large, right-angled ascending process, similar to that 

 of Scorpaena, and a short broad ligamentary process which corresponds to the proximal half only 

 of the process of Scorpaena. The distal end of the short and slender body of the bone is slightly 

 expanded, gives attachment to the hind end of the upper labial rod of gristly tissue, and lies in a 

 marked depression on the outer surface of the mandible. The bone articulates with the premaxillary 

 and vomer in the same way that it does in Scorpaena, and it gives articulation, on the dorsal surface 

 of its ligamentary process and the adjacent portions of its body and ascending process, to the anterior 



