XX] CLASSIFICATION 515 



Sub-order 6. Percomorphi. Teleostei in which the pelvic 

 bones are attached to the cleithra and in which the fins are conse- 

 quently thoracic or jugular in position. The duct of the air-bladder 

 is closed. Hard spines are developed in dorsal and anal fins and the 

 skeleton of the pelvic fin usually consists of one spine and not more 

 than five soft rays. 



Family 1. Percidae. Percomorphi in which the dorsal fin is 

 split into two fins, the front one alone having spines. 

 Ex. Perca. 



Family 2. Centrarchidae. Percomorphi in which the dorsal fin 

 is undivided. 



Ex. Micropterus. 



Family 3. Serranidae. Percomorphi in which the dorsal fin is 

 undivided and in which a .shelf supporting the eye- ball is developed 

 from one of the circumorbital bones. 



Ex. Serranw. 



Family 4. Mullidae. Percomorphi with undivided dorsal fin 

 and with a shelf for the eye-ball but with vestigial teeth and long 

 gill rakers. 



Ex. Mullus. 



Family 5. Sparidae. Percomorphi with undivided dorsal fin 

 and a shelf for the eye-ball ; the teeth are large, cutting in front, 

 crushing at the sides. 



Family 6. Labridae. Percomorphi with undivided dorsal fin, 

 no shelf for the eye-ball ; the lower pharyngeal bones fused to form 

 a single plate. 



Family 7. Scombridae. Percomorphi with a few feeble spines 

 in the dorsal fin and series of finlets behind the soft dorsal. 

 The body is attenuated behind forming a stalk for the large caudal 

 fin. 



Ex. Scomber, Thynnus. 



Sub-order 7. Heterosomata. Teleostei which habitually swim 

 lying on one side in which both eyes are twisted on to the upper 

 side of the head. Pelvic bones articulate with the cleithra, the air- 

 bladder is lost. No hard spines are developed in the fins (except 

 in one genus, Psettodes). 



Ex. Hippoglossus, Plewronectes, Psetta, Psettodes, 8olea. 



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