THE POMACEXTRIDS. 139 



Amongst those which are found on the east coast of 

 Australia may be mentioned the fish known in New South 

 Wales as the Black Trevally ( Siganns ncbulosus). This 

 is a small fish of from 8 to 10 inches in length, which, 

 though not often captured, occasionally occurs on parts of 



Fig. 52. "BLACK TREVALLY" (Siganu* 



the New South Wales coast in fair numbers. Though called 

 "Black" Trevally, this species is of a brownish colour, with 

 irregular marbled mottlings all over the body. 



A closely-allied species occurring on our coastline, is 

 Siganus javus. This is the one here illustrated. 



THE POMACENTRIDS. 



( Family : Pomacentridce. ) 



THESE are small marine fishes frequenting tropical and tem- 

 perate seas. According to Boulenger over 150 species are 

 known. Most of the species have a very brilliant coloura- 

 tion. Some live upon small marine animals, while others 

 subsist upon vegetable matter. A number of species occur 

 along the coast of Queensland, particularly in the neighbour- 

 hood of the Great Barrier Reef and a few are found in other 

 States of the Commonwealth. None of the Australian 

 Pomacentrids are at present of much economic value, but 

 some of them have very curious and interestine habits. 



