164. DULES, &C. 



are known, inhabitants of the ocean, and variously 

 distributed. Many of them possess brilliant 

 colouring. 



Dules resembles Centropristes, but has only 

 six rays in the gill membranes. The opercle is 

 spined. Several species are known, and there is 

 a slight distinction in one portion having the 

 dorsal fin perfectly entire, whereas the others have 

 a slight notch or division between the spined and 

 soft parts. An example of the first will be found 

 in D. auriga, a native of the Brazilian Seas, so 

 named, or by the French " cocher," from the third 

 spine of the dorsal fin being much elongated, and 

 supposed to resemble a whip. Of the other divi- 

 sion, a species from Java will shew the form, 

 D. maryinatuS) a small fish, of delicate silvery 

 colouring, and having the second dorsal fin tipped, 

 and the tail doubly banded at the end, with deep 

 black. 



Therapon has the anterior row of teeth upon 

 the jaws stronger than the others. Before the 

 vomer there is a single row, which fall with 

 facility when touched. The dorsal fin is deeply 

 cleft ; the preopercle and suborbitary bones are 

 toothed, and the opercle is terminated by a spine 

 stronger than almost any other of the family. The 

 swimming bladder is contracted in the centre, a 



