THE CATFISH FAMILY. 41 



good edible fish in nearly all portions of its known habitat. 

 The latter embraces almost the whole of the huge Murray 

 River system, from a comparatively short distance from 

 the mouth of the River Murray, in South Australia, right 

 up into tributaries of the Darling in Queensland, with also 

 the fresh-water portions of our northern rivers. 



In many country parts, this species is known as "J ew ~ 

 fish" ; that being likewise, the title under which it is usually 

 served up in hotels. 



In form, the Fresh-water Catfish is relatively much 

 shorter, and the body is more elevated and laterally com- 

 pressed, than in the Estuary Catfish, which it otherwise re- 

 sembles to some extent. The colour is variable, but is 

 usually of a mottled-grey or brownish. 



This species possesses the interesting habit of forming 

 a mound or nest in which to deposit its eggs. This nest 

 is formed either of sandy-grit or pebbles (if the latter are 

 available) ; and is often at least 3 feet in diameter. During 

 the process of incubation, it is jealously guarded by one or 

 other of the parents. In regard to the formation of this 

 nest, one man who had been fishing for many years on some 

 of the western rivers of New South Wales, informed me 

 that he had seen the fishes carrying pebbles in their mouths 

 to the desired spot. Others state that the mound is formed 

 by a simple fanning motion of the tail ; this fanning also 

 tending to dislodge the more minute particles, and so leave 

 the coarser particles behind for the formation of the nest. 



The Salmon-Catfishes are totally unlike either 

 of the preceding, in that they possess a well-defined 

 tail portion and an adipose dorsal fin ; as in the Salmonidce. 

 The head is very broad and depressed, and is quite hard 

 and bony above. There are six barbels around the mouth. 

 The spine of the dorsal fin, with, also, that of each ventral 

 fin, is very strong. The caudal fin is deeply forked. 



The Salmon-Catfishes deposit very large eggs, some 

 of which are nearly y^ of an inch in diameter. In all of 

 the species, great care is taken to protect the progeny. 

 Especially does this apply to some of the species in which 

 the male (more rarely the female) takes the eggs in his 

 mouth, and holds them until they are hatched. This highly- 



