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bone, the cartilage extending ventrally beyond the bone, and its ventro-lateral end projecting as a 

 small process which certainly gives articulation to the palatine cartilage at or near its hind end. Be- 

 tween this articular surface and the surface that gives articulation to the anterior end of the palatine, 

 the dorsal edge of the palatine cartilage approaches closely a narrow longitudinal ridge on the ethmoid 

 cartilage, is stronglv attached to it by fibrous tissues, and would seem to be in contact with it. The 

 anterior end of the palatine lies against the internal surface of the maxillary, posterior to the articular 

 surface on the dorsal edge of that bone, and posterior also to the little preethmoid cornu. 



Belone, it may here be stated, presents certain peculiarities in the distribution of its latero- 

 sensory canals. There is, in this fish, as is well known, a ventral body line, with a short branch line 

 running upward slightly in front of the pectoral fin. What is not known, so far as I can find, is that 

 there is a canal in the premaxillary, this canal apparentlv being an anterior and independent section 

 of the infraorbital line, which extends forward, from the base of the bone, through about one third 

 of its length. There is no slightest indication, on the external surface of the premaxillary, of a fusion 

 of latero-sensory ossicles with an underlying tooth-bearing bone ; but the evident supposition is that 

 such a fusion has taken place, the latero-sensory ossicles, of either side, together representing the 

 ethmoid of Amia and the supraethmoid of Salmo (Parker, '73), and each ossicle here being fused 

 with the corresponding premaxillary to form the ascending process of that bone. A cartilaginous 

 rostral is held between the hind ends of the premaxillaries, as it is, in Scorpaena and many other 

 fishes, between the ascending processes of those same bones. 



A further peculiarity of the latero-sensory system of Belone is, that from the point in the frontal 

 where, in other fishes that I am familiär with. the penultimate tube of the supraorbital canal arises 

 from that canal, the canal in Belone seems to separate into two parts. One of these two parts turns 

 latero-posteriorly, traverses the pterotic, and seems to end at the hind end of that bone. The other 

 part continues posteriorly to the hind end of the frontal, and there runs directly into what seems to 

 be the antero-mesial end of the supratemporal canal, which canal then continues backward as the main 

 canal. If the bone here traversed by the supratemporal canal is an extrascapular bone, as its relations 

 to the canal would indicate, a parietal bone would seem to be lacking. These conditions are so unusual 

 that I am collecting and preparing material for a proper study of them. 



Returning now to the vomer, it may be said, that in all cases where an independent preethmoid 

 bone has been properly identified, the vomer has no ascending processes, and is confined to the ventral 

 surface of the chondrocranium; and that in the Acanthopterygii and Anacanthini, in which fishes a 

 preethmoid has never been described, the figures and descriptions of the vomer show certainly that 

 it usually has, and it seems probable that it always has, a dorsal limb. In other fishes the descrip- 

 tions and figures are much too indefinite to Warrant a serious attempt at comparison. It may, however, 

 be stated that, in a general way, and so far as can be judged from therather indefinite existing figures 

 and descriptions, that where the maxillary has the relation to the premaxillary that Sagemehl de- 

 scribed as lateral (the maxillary lying as a postero-lateral continuation of the premaxillary), the vomer 

 has no ascending processes, and that where the maxillary has the position described by Sagemehl as 

 posterior (internal) to the premaxillary, the vomer has those processes. The maxillary is found 

 lateral to the premaxillary, according to Sagemehl ('84b, p. 101), only in a few families of the Physo- 

 stomi, those few families of fishes accordingly probably being the only ones in which the vomer is 

 without ascending processes. The maxillary is, according to Sagemehl, never found toothed excepting 

 in those same few families. 



