[Proc. Roy. Soc. Victoria, 32 (N.S.), Pt. I.. 1919J. 



Art. I. — Tlin Origin of the. Volcanic Tuff of Pejark Marsh 



Victoria. 



By R. henry WALCOTT 

 (Curator, Technological Museum). 



[Eead 8th May, 1919]. 



In view of the discovery of a native implement associated ■with, 

 fragments of bones of extinct marsupials under volcanic tuff at 

 Pejark Marsh, near Terang, by Mr. A. J. Merry, i increased 

 interest is attached to the task of ascertaining the probable age- 

 and origin of the tuff. 



For this reason the opportunity was taken, while supervising^ 

 some excavations being made at the Marsh, in 1909, in search of 

 further evidence of man's antiquity, of paying a few hurried 

 visits to various places in the neighbourhood likely to bear upon 

 the subject. The following notes are principally the result of 

 information so gained, but, as the time devoted to field investiga- 

 tion was unavoidably very limited, they must of necessity be 

 brief, and perhaps omit some matter of value in deciding the issue 

 in question. 



An account of the excavations referred to, and of the occur- 

 rence of the tuff has already appeared. 2 It might be mentioned 

 here, however, that the tuff is seen as a fine-grained bedded deposit, 

 from 15 to 24 inches thick, along a drain made to carry the water 

 away from the Pejark Marsh. The tuff has Ijeen laid down in an old 

 swamp, now represented by a stiff, black clay bed, and abundant 

 leaf impressions are present in the lower layers of the tuff. Rest- 

 ing on the tuft' again, comes the heavy, black soil of the present 

 marsh, some two or three feet in thickness. 



The tuff is locally known as " sandstone," and is also called* 

 " sandstone tuff," on the quarter sheet No. 8 N.E. (New Series),, 

 of the Geological Survey of Victoria. 



Previousi reference to the deposit has been made by Professor J. 

 W. Gregory .3 when he states : " The broad down-shaped hill to the- 

 south-west of Camperdown, and the plains between Terang and 

 Noorat, are formed of re-deposited, bedded tuffs. The low cliffs 



1. An account of this discovery has not yet been published. The implement 



is in the possession of the National Museum, Melbourne. 



2. Spencer and "Walcott, "The Origin of Cuts on Bones of Australian 



Extinct Marsupials." Proc. Roy. Soc. Vict., pt. I., 1911, pp. 92-123. 



3. The Geography of Victoria, Melb., 1903, p. 192, and revised edition, 1912,. 



p. 204. 



2 



