192 



PISCES. 



Naucrates (Cuv.). Pilot-fish. As in Centrolophus, 

 but there are free spines before the dorsal and anal; 

 sides of the tail keeled. 



1ST. ductor. Fig. 302 ; J n. s. 



Xiphias (Linn.). Sword-fish. One dorsal very 

 high in front ; ventrals wanting ; anal large ; 

 caudal high, and crescent-shaped ; upper jaw pro- 

 longed into a hard sword-like beak. 

 X. gladius. Fig. 303 ; -fan.8. 



303 



Scomber (Linn.). Mackerel. Body gracefully 

 shaped, smooth, brilliant, clothed with minute 

 scales; two dorsals remote from each other; second 

 dorsal and anal cut into triangular finlets ; tail 

 crescent-shaped. 



S. scombrus. Fig. 304 ; J n. s. 

 colias. 



Thynnus (Cuv.). Tunny. Large scales on the 



