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TELEOSTEI 



CHAP. 



Asprotilapia, JEretmodus, Plecodus, Pseudctroplus. American : 

 Acara, Heros, Hygrogonus, Cichla, Crenicichla, Chaetobranchus, 

 Geopliagiis, Symphysodon, Pteropliyllum. Indian : Etroplus. 



No part of the world surpasses Lake Tanganyika in variety of 

 generic and specific types of Cichlidae, the fish-fauna of this 

 great lake being in great majority made up of members of this 

 family. 



FIG. 411. Distribution of the Cichlidae. 



Priscacara, from the Eocene of North America, is the only 

 extinct genus which can be referred to this family. 



Fam. 34. Pomacentridae. A subocular shelf ; entopterygoid 

 present ; palate toothless ; teeth conical or incisor -like ; lower 

 pharyngeals completely united into one bone. Vertebrae with 

 transverse processes from the fourth or fifth ; ribs inserted on the 

 transverse processes, when these are present. A single nostril 

 on each side. Gill-membranes free from the isthmus ; 5 to 7 

 branchiostegal rays ; gills 3^ ; pseudobranchiae present. Dorsal 

 fin elongate, with numerous strong spines ; anal with 2 spines 

 only. Ventral fins with 1 spine and 5 soft rays. 



Small fishes of the tropical and warm seas, resembling the 

 Chaetodontidae in form and mode of life, likewise usually 

 of brilliant coloration ; in structural characters intermediate 

 between the Cichlidae and the Labridae. They feed chiefly on 

 small marine animals, but the species with incisor-like teeth are 

 entirely or mainly herbivorous. Over 150 species are known. 



Principal genera : Heliastcs, Azurina, Amphiprion, Premnas, 

 Dascyllus, Pomacentrus, Glyphidodon, Microspathodon. 



