160 



PISCES. 



Sub-Class II. OSSEI. 



Skeleton formed of bone ; skull composed of 

 many distinct pieces. 



Jaw-bones soldered together . . Fledognathi. 



Jaw-bones free : 



Gills arranged in tufts .... Lophobranchii. 

 Gills in comb-like fringes : 



Fin-rays soft, jointed .... Malacopterygii. 



Fin-rays (partly) spinous . . Acanthopterygii. 



Order I. PLECTOGNATHL 



Skeleton partly of bone, partly of cartilage ; 

 jaws formed by the soldering together of the 

 maxillaries and tnter-maxillaries ; arch of the 

 palate united to the skull ; mouth small, almost 

 motionless ; gill-opening small ; body usually short 

 and thick. 



240 



Balistes (Linn.). File-fish, Body compressed, 

 covered with lozenge plates ; first dorsal spinous ; 

 cutting-teeth in both jaws. 



B. capriscus. Fig. 240 ; J n. s. 



