492 



the caudal peduncle. Anterior dorsal and anal fins a little 

 produced ; caudal either truncate, slightly emarginate, or 

 slightly rounded, according to the extension of the exterior 

 rays. 



Colour. — Sides of carapace and caudal peduncle witli 

 more or less sinuous dark bars, which become irregular and 

 anastomosing on the supero-posterior portions of the sides; 

 they are variable in number, there being about twelve on each 

 side in a small and twenty-one in a larger specimen; they 

 are oblique on the sides of the snout and about as wide as or 

 slightly wider than the light interspaces, but are almost 

 horizontal on the sides and on the caudal peduncle, and 

 usually become broader on the latter. Bases of the dorsal, 

 anal, and pectoral fins with oblique dark bars, which vary in 

 number and disposition. Fins plain, the anterior dorsal and 

 anal rays slightly darkened. 



Described from five specimens, 101-135 mm. long. The 

 smallest is in general agreement with Richardson's figure, 

 though the dark bands are not wider than the interspaces as 

 he shows them, and the abdomen is less angular, and its depth 

 not so great. Our largest specimen, which is figured, differs 

 in having the bands more numerous and the snout gibbous 

 in front of the eyes. 



Giinther has united A. flavigaster with A. ornata, basing 

 his opinion upon an examination of the types of both forms. 

 We scarcely think tlie specimens here described and figured 

 can be regarded as forms of A . ornata, since they differ from 

 that species in having the snout oblique instead of subtruncate 

 in adults, and the dark bars on the caudal peduncle single 

 instead of in pairs. If A. flavigaster is correctly associated 

 with A. ornata, our specimens should apparently be identified 

 as .4 . amoena, Castelnau. 



Loc. — Tamar River, Tasmania; off the mouth of the 

 Murray River, South Australia, 20 fathoms ; nine to ten miles 

 west of Glenelg, Gulf St. Vincent, 10-12 fathoms. 



Kentrocapros, Kaup. 



Acerana, subgenus Kentrocapros, Kaup : Arch, fur Naturg., 

 1855, xxi., p. 220 (Ostracion hexagonus, Thunberg). 



This genus is apparently valid. It is allied to Aracana, 

 having the carapace flat above, but the supralateral ridge 

 bears only one large spine ; there is a mediolateral ridge armed 

 with more or less numierous spines, and the abdomen is 

 scarcely keeled. 



Ostraciofi hexagonus, Thunberg, is synonymous with 

 0. acideatiis, Houttuyn, according to Giinther and Jordan and 



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