REVISION OF THE GENUS EUASTACUS 
25 
entering the Murray between Cobram and Swan Hill. The 
principal of these is the Goulburn and its tributaries. E. 
elongatus is found in the Upper Goulburn and its tributaries 
FIG. I. 
Map illustrating Gregory’s theory of river development in Victoria. 
from the north and east (the J amieson, the Howqua and the 
Delatite Rivers), but in tributaries from the south, such as 
the Acheron and Yea Rivers and King Parrot Creek, 
elongatus gives place to yarraensis, which occurs also in all 
