BY W. MACLEAY, F.L.S. 367 



1100. ACAXTHIAS BlAINVILLEI, KisSO. 



Mull. & Henle, p. 84.— Dum., Elastnobr., p. 438.— Gunth., Cat. 



Fishes VIII., p. 419. 



Eesernbling^L vulgaris, but with the first dorsalfin conspicuously 

 in advance of the inner posterior angle of the pectoral. 



New Holland (Gunther). 



1101. ACANTHIAS MEGALOPS, 11. Sp. 



Head flat ; snout long, tapering and rounded in front, the 

 distance from the mouth to the snout about equal to the width 

 of the mouth, which is moderately crescent-formed and has a 

 straight oblique groove at the angle. The nostrils are near 

 the snout, and twice the distance from the mouth. The orbital 

 cavity is of great length, about equal to its distance from the 

 point of the snout, and its height is less than half its length ; 

 close to and above the posterior corner of the eye is a rather 

 large oblique spiracle. The first dorsal fin is placed in advance 

 of the vertical from the posterior angle of the pectoral ; the 

 ventrals are placed opposite the middle of the space between the 

 two dorsals. A very conspicuous keel runs along each side of 

 the tail immediately below the median lateral line. Colour 

 uniform greyish-brown. 

 I Port Jackson. Length two feet. 



Genus Isistius, Gill. 

 Two very small dorsal fins, without spine, the first nearly 

 opposite to the ventrals ; no anal fin. Skin uniformly granular. 

 Mouth transverse ; a deep straight groove at each angle of the 

 mouth, the fold which covers it runs round the whole margin of 

 the upper jaw ; an upper and lower free lip besides. Nostrils 

 nearly in front of the snout. Upper teeth small, narrow, 

 lanceolate, the lower much larger, triangular, nearly erect, with 



