56 



A NEW FORM OP THE GENUS THERAPON. 



Locality, neighbourhood of Brisbane, common in most of the 

 creeks. Its habits are essentially aquatic; it may with caution be 

 often observed sitting on the snags beside the water, into which it 

 drops at the slightest alarm. Occasionally it rises to protrude 

 its nose above the surface, but like its relative Grammatophora 

 muricata^ and perhaps others of the sept, it can remain at the 

 bottom for a long period. Received also from the Tweed River. 



Our fresh-water fish are as yet but very imperfectly known and 

 we are therefore always glad to welcome a new acquaintance in 

 this division of our fauna. Dwellers on our creeks and lagoons 

 would, without much trouble, earn our thanks by sending for 

 examination even dry specimens of all the fish to be caught in 

 them, and would doubtless find that they could frequently enjoy 

 the credit of enlarging the field of knowledge in this direction. 

 This has been exemplified by Mr. Ling Roth, of Mackay, who 

 has been at the pains of conveying from Lake Elphinstone the 

 fish which awaits description. Lake Elphinstone is a sheet of 

 water about six miles long and two miles broad, situate between 

 Nebo and the Suttor River. It lies in a land locked basin, and 

 is without an afliiuent, but, notwithstanding that it apparently 

 receives only the water shed from the very limited slopes around 

 it, its contents are not diminished by prolonged drought to any 

 very great extent, and they are at all times particularly turbid. 

 We might almost suspect the presence of mud springs at the 

 bottom — apart from turbidity there may also be something in the 

 water still more inimical to animal, or at least to fish life, for Mr. 

 Ling Roth states that the fish under notice is the only one to be 

 found in it. If so, the monopoly it has of the lake may perhaps 

 be explained by the great adaptability to circumstances shewn by 

 the whole genus to which it belongs. This group of Australian 

 perches contains a goodly number of species of which some are 

 littoral sea-fish, others inhabit brackish waters, and others prefer 

 pools and lakes. Their occupation of a habitat unsuitable to 

 other fishes may result from this elasticity of constitution. The 

 Therapons form a very natural group, a pretty strict uniformity of 



ON A NEW FORM OF THE GENUS THERAPON. 



Br 0. W. De Vis. 



