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dorsal limb of the vomer, and was described by me as the dorsal articular head of tlie bone. The otber 

 is represented in the little process which not only gives Insertion to the ethmo-maxillary ligament, 

 but also articulates, by its antero-mesial aurface, with the articular process of the premaxillary. In 

 Amia, the process is not evident, nor is it in Salmo (Parker, '73), Esox, Citharinus (Sagemehl, '84b), 

 Hydrocyon (Sagemehl, '84b), Elops (Eidewood, '04a), Megalops (Ridewood, '04a), Albula (Ridewood, 

 '04a), Mormyrops (Ridewood, '04b), Notopterus (Ridewood, '04b), or Gymnarchus (Erdl, '47). But 

 in several of these fishes there is a bend in the maxillary, near its proximal end, and at this bend 

 there is an eminence on the bone which may quite probably represent the well-developed process 

 of the Acanthopterygii and Anacanthini. This can only be determined when these fishes shall have 

 been much more carefully described than they have been up to the present time. 



In Gonorhynchus Greyi, according to Ridewood ('05 b), ,, There is no articulation between 

 the ethmoid region of the craniura and the maxilla, nor between the ethmoid and the premaxilla". 

 The premaxillary, as shown in Ridewood's figures, is here without either ascending or articular 

 processes, the maxillary is without ascending process, the vomer is apparently without ascending 

 processes, and the preethmoid (septomaxillary), if present, is apparently fused with the mesethmoid. 

 This all seems to need further examination. 



NASAL SAC. 



The nasal sac of Scorpaena is large, and has two large diverticula. The posterior surface of 

 the sac lies against the anterior surface of the ectethmoid, occupying the space between the preocular 

 spinous ridge and the lateral edge of the arm of the bone. The posterior nasal aperture lies at the 

 tapering dorsal end of this portion of the sac, immediately lateral to the preocular spinous ridge; 

 the anterior aperture lying slightly anterior to it, approximately between the summit of the meseth- 

 moid process and the dorso-lateral corner of the arm of the ectethmoid. The anterior opening of the 

 olfactory canal through the antorbital process lies in this same region, approximately ventral to 

 the anterior edge of the posterior nasal aperture. As the olfactory nerve issues from its canal, it turns 

 dorsally, at the same time spreading in a postero-anterior direction, and, pushing the floor of the 

 sac upward, forms a stout vertical partition which rises from the floor and anterior wall of the sac 

 and reaches upward nearly to its roof. It bears, on its summit, a rosette of sensory tissue, this 

 rosette lying directly beneath the anterior nasal aperture. The floor of the nasal sac extends forward, 

 on either side of this sensory partition, to the level of the summital edge of the ascending process 

 of the maxillary, which edge abuts against the anterior end of the partition. The floor of the nasal 

 sac is thus here U-shaped. The lateral leg of the U lies directly above the open oval space, already 

 described, that lies between the lateral edge of this part of the skull and the dorso-mesial edges of 

 the lachrymal and palatine, this space being closed, ventrally, by the lining membrane of the 

 mouth cavity. 



From each leg of the U-shaped nasal sac, an important diverticulum arises, these diverticula 

 doubtless being the ,, nasal sacs" or ,,reservoirs" that Kyle ('00) says are found in the Scorpaenidae, 

 but which I cannot find that he describes. The diverticulum that arises from the lateral leg of the 

 U is the larger one of the two. It passes beyond the lateral edge of the skull, and there lies in the 

 space enclosed between the lachrymal above, and the palatine below. It has a short posterior Pro- 

 longation and a longer anterior one. The posterior Prolongation lies along the ventro -lateral edge 

 of the arm of the ectethmoid, between the two articular surfaces on that edge. The anterior end of 



