266 Charles Fenner : 



DjL'^ri^var^h or Deep Creek, and (tu a less extent) the Toolam 

 Toolern Creek, are deeper and steeper-sided than those flowing^ 

 northward from this divide. 



While the three creeks just referred to flow southward to the 

 Werribee, there is a fourth parallel stream going southward — the 

 Kororoit Creek — which turns east on reaching the low basalt plains, 

 and enters the Bay independently. This course was evidently 

 selected owing to minor irregularities in the surface of the volcanic 

 plains. To follow the divide between the Werribee and the Koro-- 

 roit Creek basin, we must now descend from the Gisborne high- 

 lands, and travel southward. 



The western branch of the Kororoit Creek, in the higher levels, 

 is very closely related to the eastern branch of the Toolern Creek, 

 and minor captures appear to have taken place. On the plains, 

 from near Melton down to the sea, the divide is low, with few and 

 small irregularities similar to that between the Werribee and the 

 Little River already described. Between Kororoit Creek and the 

 Werribee a small valley (the Skeleton Water Holes) comes from the 

 slightly higher country about Mts. Cotterill and Atkinso'n, and 

 helps to drain tlie plains, flowing directly into the sea. 



(ii.) The Werribee River in relation to its 0W7i tributaries. 



The complex nature of the Werribee and its tributaries will be 

 seen from a reference to the special river map (Plate XII A.), and 

 the grade profiles of the Werribee (Plate XII B). It may be here ex- 

 plained that the plan of the Werribee and its tributaries has cer- 

 tain imperfections; it is based on the county plans of Bourke and 

 Grant, and where the streams were unmarked in those maps, an 

 effort was made to complete the map from other sources. The 



Fig. 23— Oliaracteristic longitudinal section, showing relative grades of a 

 stream and its tributaries, after Nuijsbaum (ref. 32). 



general plan of the main streams is quite correct, but exactness is 

 lacking in the tributaries of Goodman's Creek, the upper Pyrete, 

 and the Lerderderg. 



It may also h^ explained that tlie grades of tlie rivers and creeks 

 were plotted from levels supplied by the published maps and field 

 notes of the Military Surve(v% supplemented in the unmapped parts 



