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SOME NEW GENERA AND SPECIES OF FISHES. 



By J. Douglas Ogilby. 



HETERODONTID^. 



Gyropleurodus. 1 sp.nov. 



Appended is the description of the teeth of a cestraciont shark 

 caught some years ago off Manly Beach and preserved on account of 

 their beauty. It will be seen from the desci'iption that the dentition 

 differs greatly from either of the Australian species, but approaches 

 that of Gyropleu7'odus gcdeatus in the uninterrupted divergence 

 of the rami of the jaws, while differing in the large number 

 of short and strongly carinated lateral teeth. I am unwilling to 

 describe this species as new on the evidence of this pair of jaws 

 alone, but wish to call attention to the possibility of a third 

 species being found in our waters, and to impress on such of 

 my readers as may have the opportunity the necessity for examin- 

 ing all specimens of Bullhead Sharks for a similar pair of jaws, 

 and, when found, to preserve the entire animal. The only species 

 with which it could be confounded (besides galeatus) is Gyropleu- 

 rodus quoyi, Fi'eminville, a little known species from the Gala- 

 pagos Islands; it is, however, possible that these jaws belong to 

 an adult G. galeatus, in which the two elongate molars have been 

 more or less symmetrically broken up into a number of small ones. 



In the upper jaw the anterior teeth are stout and conical 

 without or with scarcely a trace of a basal cusp; passing back- 

 wards along the sides the bases of the teeth become broader and 

 the cusp more and more strongly inclined backwards, until they 

 almost insensibly merge into the strongly carinated molariforni 

 lateral teeth, of which there are about ten whorls on one ramus 

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