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TRANSACTIONS OF THE AMERICAN PHILOSOPHICAL SOCIETY 



preopercular agrees with that of the Carangidse in being much less expanded posteriorly 

 than that of typical scombroids. In brief, while Coryphcena appears to belong in the 

 carangoid section rather than in the scombroid, its skull as well as its vertebrae, ribs, fins, 

 caudal pedicle and tail, are all less specialized, more primitive, than those of the scombroids. 

 Tate Regan (1909Z>, p. 69) notes that "the structure of the pectoral arch and of the caudal 

 fin is as in the Carangidae, to which family the Coryphaenidse may be related." He notes 

 also that Brama and Mene appear to be related to each other and that the cranium of 

 Brama (Fig. 182) is strikingly similar to that of Coryphcena. 



Stromateoids. — Apparently allied with the carangoid stem are stromateoids, which 

 have teeth in the gullet. In Rhombus (Fig. 184) the bony bases of the median fins are 

 tied together in a continuous line which suggests the outline of Luvarus. 



epiot 



oryphasna hlppurus 



Fig. 183. Coryphtena. 



Luvarus. — Apparently related to Rhombus is the rare Luvarus, the skeleton of which 

 is described and figured by Waite (1902). The fish somewhat resembles a bonito in general 

 outline, the upper and lower borders of the skeleton being defined by strong longitudinal 

 arches formed by coalescence of the bases of the interneurals and interhaemals, respectively. 

 The vertebrae recall those of Coryphcena. The skull roof (Fig. 185) is depressed to the 

 plane of the vertebral column by the steeply developed epaxial muscles which extend for- 

 ward to the ethmoid, forming a high crest. The large eye therefore lies well below the 

 level of the backbone. The mouth is small, slightly upturned and apparently not pro- 

 trusible. The suspensorium is curved far forward. The large preopercular and very 

 large opercular are produced downward and backward. 



