252 Proceedings of tlte Royal Society of Victoria. 



extending little, if any, higher up the river than the east end of 

 Anderson Street cutting. 



The section in the north cutting shows apparently that the 

 basalt margin occurs in the cutting not reaching the south 

 side except at the south-east end, and that the shelly marls 

 v.'ere deposited against its side. Over these the river brought 

 down quantities of alluvium, which accounts for the absence of 

 marine shells and presence of roots and vegetable matter. There 

 does not appear to be any unconformity between the alluvium 

 and the shelly marl, the latter grading off into alluvium as the 

 land was gradually I'aised and brackish and fresh water took the 

 place of salt water. 



The age of the basalt is, however, still a moot point. If it be 

 regarded as overlying the shelly marls then its age is much 

 younger than generally supposed, and brings it nearly to recent 

 times, since the shells found in the marl are identical with, or 

 but very slightly different from, those now living in the Bay. 



DESCRIPTION OF PLATES XLI. and XLII. 



Plate XLI. 



Geological map of the Yarra Valley near the Botanical Gardens, 



Melbourne. 



Plate XLII. 



Geological sections to illustrate map. 



