42 FISHES OF AUSTRALIA. 



interesting habit may be observed in the larger of our 

 common Salmon-Catfishes (Galeichthys thalassinus') in a 

 number of rivers : notably the Clarence and the Richmond. 

 The discovery of the adults with their mouths full of eggs, 

 has given rise to the idea, prevailing in some quarters, that 

 these fishes eat their own spawn. The smaller species 

 (Galeichthys australis), which grows to a length of about 

 18 inches, builds nests upon the sandy beds of rivers, making 

 circular basin-like excavations about 20 inches in diameter ; 

 at the bottom of which the eggs are laid, being then covered 

 over with several layers of large stones. As will be seen, 

 this habit is very like that practised by the Fresh-water 

 Catfish, before referred to. 



Fig. 14. Forepart of SALMON-CATFISH (Galeichthys australis). 



The Salmon-Catfishes are of little value as food-fishes. 



In one genus of Catfishes (Aspredo} which does not 

 occur in Australian waters, during the breeding season, the 

 skin of the lower parts of the female becomes quite soft, 

 thick and spongy. After depositing the eggs, the female 

 lies over them and presses them into the skin, in which 

 they remain firmly embedded, until the embryo is hatched 

 out. 



Quite a large book could be written dealing with the 

 efforts of Catfishes to ensure the continuity of the species. 



