PERCIDiE. 389 



More than thirty species are known of this genus, which 

 bear so close a resemblance to one another that their distinc- 

 tion is rather difficult. They live in the seas between the 

 Tropics, and some, perhaps all, of the species enter fresh 

 water. Very rarely they exceed a length of ten inches ; 

 nearly all have a plain silvery coloration. The coalescence 

 of their lower pharyngeals renders their systematic position 

 rather uncertain, and, indeed, some Ichthyologists have referred 

 them to the Pharyngognaths. 



ScOLOPSis. — Body oblong, covered with scales finely serrated 

 and of moderate size. Jaws nearly 

 equal in length anteriorly ; cleft of the 

 mouth horizontal. Teeth villiforra, 

 without canines ; palate toothless. One 

 dorsal fin. Formula of the vertical 

 fins : D. V A. f. Caudal fin forked. 

 Prseoperculum distinctly denticulated ; 

 infraorbital ring with a spine directed 

 backwards. Branchiostegals, five. ^'S- 160. -Infraorbital spine 



of Scolopsis monogramma. 



Marine, and of small size. Twenty-five species are known 

 from the tropical parts of the Indo-Pacific. Heterognatliodon 

 is an allied genus, but without the infraorbital sj)ine. 



Dentex. — Body oblong, covered with ctenoid scales of moderate 

 size. Cleft of the mouth nearly horizontal, with the jaws equal 

 in length anteriorly. Canine teeth in both jaws ; palate tooth- 

 less. One dorsal fin. Formula of the vertical fins : D. \%\\^ 

 A. -s?Tr. Caudal fin forked. Prseoperculum without serrature ; 

 prseorbital unarmed and broad, there being a wide space between 

 the eye and the cleft of the mouth. Cheek covered by more 

 than three series of scales. Branchiostegals, six. 



Marine Fishes, rather locally distributed in the Mediter- 

 ranean, on the south coast of Africa, in the Red Sea, East 

 Indian Archipelago, and on the coasts of China and Japan. 

 About fourteen species are known, some of which attain a 



