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Fishery Bulletin 90(1). 1 992 



but in Acanthoeybium the right and left lobes are about 

 the same size. Two efferent vessels lead directly from 

 the anterior surface of the liver into the sinus venosus. 



The stomach is sometimes visible in ventral view, 

 partially covered by the liver and caecal mass, but often 

 completely hidden. Stomach contents included crusta- 

 ceans and small fishes. 



The pyloric portion of the intestine arises from the 

 anterior end of the stomach, where the main branches 

 of the pyloric caeca join the intestine. The caeca branch 

 and form a dense dendritic conglomeration, the caecal 

 mass. The intestine continues posteriorly as a simple 

 straight tube to the anus. A straight intestine is also 

 found in Acanthoeybium (Fig. 5b) and S. niphonius, but 

 all other species of Scomberomorus have folds (2 or 4) 

 in the intestine (Fig. 5a). 



Osteology 



The osteological description is divided into five sections: 

 skull, axial skeleton, dorsal and anal fins, pectoral 

 girdle, and pelvic girdle. Osteological terminology and 

 organization generally follow that of Collette and Russo 

 (1985b). 



Skull Description of the skull is presented in two sec- 

 tions: neurocranium (Figs. 6-9) and branchiocranium. 



Neurocranium Following a general description of 

 the neurocranium, the four major regions are dis- 

 cussed: ethmoid, orbital, otic, and basicranial. 



General characteristics In dorsal view (Fig. 6), 

 the neurocranium of Grammatorcynus is more or less 

 triangular in shape, narrow at its anterior margin. 



