250 Proceedings of the Royal Society of Victoria. 



The lower portion consists of flattened, rounded and subangular 

 pebbles of the local niudstones, claystones and sandstones ; the 

 upper portion of rounded pebbles of these rocks and of quartz in 

 addition. All these pebbles are cemented together by slightly 

 ferruginous sand. Overlying these are yellow, red, and white 

 mottled fine sandy clays or clayey sands. This conglomerate is 

 undoubtedly of local origin and derived from the Silurian rocks, 

 while that in the east end of the north cutting is also local, but 

 derived from both Silurian and basalt, thus, apparently, showing 

 that the stream which made the pebbles ran between these two 

 points over the contact of these two rocks, and, therefore, along 

 about the same course as the present Yarra. The single outcrop 

 of basalt south of the river occurs a few yards north of the point 

 where the conglomerate is visible, but its relation to this band 

 cannot be seen owing to the debris from the Silurian rocks from 

 the cutting that has been piled on to it. 



After getting through this Silurian point into the river in the 

 south cutting, work has been extended only a short distance 

 further up stream by slicing a strip of the southern bank for 

 about 100 feet back from the river. In this portion, where work 

 has been suspended at the Punt Road foot bridge, the excavation 

 is only about 12 feet deep. About 8 feet of the upper portion is 

 simply ordinary alluvium, but 4 feet on the bottom contain a 

 few large pieces of carbonised wood and other fragments of 

 vegetation. No basalt or shell marl are visible here. 



The recent deposits in the south cutting presented some rather 

 interesting features. In the alluvium and marl there are 

 numerous very thin layers or partings, varying from a thread to 

 I inch in thickness, having a pronounced dip, ranging from N. 60° 

 W. to N. at from 7" to 9° 30'. These layers on being examined 

 proved to be very tine white sand, the marl caking off in a clean 

 manner when disturbed. Most of them had white exudations of 

 salt and what appeared to be magnesium chloride and in several 

 cases small fragments of barnacles were visible. Shells were 

 sparingly interspersed through the lower portions of the marl 

 and small patches of barnacles occurred. The changing dip of 

 the beds on the north side of the south cutting seems to indicate 

 that they were laid down over a small rise by a gentle current 

 not strong enough to cut through them and cause current 

 bedding. 



