Phrntij River and Amlersuns, Creek. 



171 



a valley too broad in proportion to its length. The low ridge 

 between the western end of Parson's Gully and the Anderson's 

 Creek Gorge represents the approximate level of the valley 

 when the upper part of Anderson's Creek and Parson's Gully 

 were one continuous stream ; and the height of this ridge above 

 the present Anderson's Creek (about 100 feet) represents the 

 minimum vertical erosion since the capture. It is somewhat 

 ditiicult to fully understand why the capturing stream should 

 so successfully have crossed the hard rocks, but on the other 

 hand the low ridge near the entrance to the gorge, and the 

 other facts mentioned, can only be satisfactorily accounted for 

 by the explanation given above. 



Various points on Fifth Hill give excellent views of the gorge, 

 and of the once continuous vallev to the north and south. 



OldPlEs-?/ /\/0lirHE/^ P/^£S£/<,r 

 ' VALLty Tongue-" /le/vrrA 



p. ,1 /<(.•«. A i 

 Uld L^Onwur. 



■\->r /iEvJERBASALT j j | OiDEfiRoad 



FlG.2 



EXPLAXATTOX OF PLATES. 



Plat;: XXXI. 



Map compiled from the Geological Survey Quarter Sheets of 

 the district, with some later topographical information. The 

 rocks older than the newer basalt have for the purposes of the 

 paper been grouped together. The numerals indicate the heights 

 of some railway stations and points along the Yan Yean Pipe 

 Track. The unshaded portions represents the newer basalt 

 (except the Yan Yean and Toorourrong Reservoirs, which occur 

 in Silurian country). 



Plati: XXXIT. 



Sketch map of the "Warrandyte district, compiled partly from 

 Quarter Sheet 40 N.W. 



