302 SYNOPSIS. 



256 ; Yarr. Brit. Fish., i. p. 164; Pern. Brit. Zoo?., ill 

 p. 216, pi. 30. 



GEN. XXVI. NAUCRATES. Body thick and covered with small 

 scales ; dorsal single and elongated, and both it and the anal 

 with free spinous rays placed in advance of them ; sides of the 

 tail keeled ; jaws equal. 



Sp. 49. N. ductor. Pilot-fish. Snout somewhat rounded, 

 lower jaw slightly projecting; teeth very small and nu- 

 merous, a single strong tooth in front of the vomer and 

 another on the tongue ; dorsal and anal fins ending on the 

 same line ; caudal acutely forked ; colour greyish blue, 

 glossed with silver, with five broad, regular, dark bands 

 round the body ; pectoral fins clouded with white and 

 blue, ventral dusky. CW. & Vol., viii. p. 312, pi. 232; 

 Yarr. Brit. Fish., i. p. 170. Gasterosteus ductor, Linn. 

 Centronotus ductor, Jenyns^ Brit. Vert., p. 365. 

 GEN. XXVII. CARANX. Body covered with small scales, 

 the lateral line cuirassed with large imbricated scales, forming an 

 elevated ridge, especially in the posterior portion ; dorsals two, 

 distinct, the anterior having a reclined spine in front of it ; free 

 spines before the anal. 



Sp. 50. C. tradiwrus. The Scad, or Horse-Mackerel. Lower 

 jaw projecting considerably beyond the upper ; lateral line 

 parallel with the back till opposite the commencement of 

 the second dorsal, where it bends obliquely downwards ; 

 second dorsal and anal fins nearly of equal length and the 

 same shape, in front of the latter two sharp spines united 

 by a membrane, caudal deeply forked ; colour leaden-grey 

 variegated with blue and green* silvery beneath ; opercu- 

 lum with a black spot. Lacepede, Cuv. <$ Fa?., ix. p. 1 1 , 

 pi. 246. Scomber trachurus, Linn. Scad, Penn. Brit. 

 Zool, iii. p. 363, pi. 62; Don. Brit. Fish., pi. 3. 

 GEN. XXVIII. CENTROLOPIIUS. Dorsal fin single and elon- 

 gated, commencing on a line with the pectoral, anal fin half a 

 long as the dorsal ; teeth small and numerous, the palate with- 

 out teeth ; tail not keeled. 



Sp. 51. C. pompilus. Black-fish. Body compressed, the 



