— 160 — 



end of the maxillary process of the palatine. It does not give support, at any point, to the lachrymal ; 

 but a short, strong ligament extends from the summit of the ascending process of the bone to the 

 dorsal edge of the lachrymal, this ligament having its attachment also in part on the lachrymo-palatine 

 process of the nasal. 



The LIGAMENTS associated with the upper jaw were not properly investigated, the smaller 

 specimens not being suitable for this investigation, and the skeletons of the larger specimens having 

 been prepared, as already stated, without special attention being given to any of the soft parts. The 

 ethmo-maxillary ligament is well developed, even in the small adults, and has already been described. 

 The rostro-palatine ligament is also well-developed and has the usual relations, but, because of the 

 shortening and deepening of the snout, it lies in a nearly horizontal position, the position being the 

 more nearly horizontal, the smaller the specimen. The tendon of that part of the adductor mandibulae 

 muscle that has its insertion on the maxillary in the other fishes of the group, is here also well devel- 

 oped, and, the posterior portion of the ligamentary process of the maxillary not being developed, 

 is inserted on the dorsal surface of the body of the bone near its proximal end. The naso-maxillary 

 ligament is a short stout ligament that extends from the lachrymo-palatine process of the nasal to the 

 outer end of the ascending process of the maxillary. The vomero-palatine and lachrymo-palatine 

 ligaments are reduced, because of the articulating contact of the parts concerned, to tough fibrous 

 or ligamentous tissues that hold the articulating surfaces together. No other definite ligaments 

 were recognised in the dissections, but in the sections of the small specimens there is a well developed 

 ligament that extends from the lateral surface of the rostral to the dorsal end of the ascending process 

 of the maxillary; and another that extends from the ventral (here posterior) edge of the ascending 

 process of the premaxillary to the proximal end of the maxillary, this ligament traversing the narrow 

 space between the rostral and the articular process of the premaxillary. 



The VOM ER differs somewhat from the bone in the other fishes of the group, and it can 

 be best understood by stating, at once, that this part of the skull of Dactylopterus has been so greatly 

 flattened that the ascending processes of the vomer have apparently been j:>ressed down upon and 

 become completely fused with the underlying body and lateral processes of the bone; the antorbital 

 cartilage being, so to speak, squeezed out from between the dorsal and ventral limbs of the bone. 

 As a result of this, the vomer is a solid bone of the shape shown in the figures, with a convex ventral 

 and a concave dorsal surface, the exposed portion of the latter surface being about two-thirds as 

 long as the ventral surface of the bone, and representing the ascending processes of the bone. This 

 part of the dorsal surface of the bone forms the floor of the anterior portion of the rostral Chamber, 

 is grooved in the middle line to receive the rod-like prenasal process of the antorbital cartilage, and, 

 lateral to that groove, on either side, has a slightly raised and flattened surface which gives articulation 

 to the ascending process of the corresponding maxillary. The middle portion of the bind edge 

 of this part of the vomer abuts against the anterior edge of the antorbital cartilage, but whether 

 it is in synchondrosis with that cartilage or not, could not be definitely determined. Apparently 

 it is not, the vomer of Dactylopterus seeming to be a purely dermo-membrane bone, and not apprec- 

 iably overlapping or having perichondrial relations to the dorsal surface of the adjacent cartilage. 

 Lateral to the antorbital cartilage, on either side, the thin hind edge of this part of the vomer — here 

 apparently formed by the fusion of the lateral and ascending processes — suturates with the pedicle 

 of the corresponding ectethmoid, the hind end of the «hört body of the bone underlying the antorbital 

 cartilage and suturating with the parasphenoid. 



