Ill 



THE LAKE DISTRICT 



83 



tions, is studying this subject, which is of great 

 importance in connexion with the probable deriva- 

 tion of the fauna in the southern hemisphere. 



The shallowness of the Great Lake has already 

 been mentioned, the average depth being about 

 fifteen to twenty feet, and there are not known to 

 be any deep holes ; in consequence, when the 

 weather is rough the mud on the bottoms is very 



Fig. 20. Neoniphargus ripensis, from the Great Lake. 

 (Four times natural size). 



easily stirred up, and the waters are always more or 

 less cloudy and discoloured. It is probably due to 

 this fact that the amount of floating life in the water, 

 technically known as plankton, and consisting chiefly 

 of small Crustaceans, Rotifers, Algae, and Protozoa, 

 &c., is very small. The shallowness of the lake also 

 leads me to discredit the stories which are told of 

 a gigantic and mythic monster, the Bunyip, which 

 is said occasionally to rear an almost human 

 face above the waters and utter strange sounds, 

 although the presence of such a being is attested 



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