60 Proceedings of the Royal Society of Victoria. 



of Henderson's Flat. Horizontal bands of limestone were 

 noticed, as we crossed this flat, high up on the bank, and it was 

 at first taken for granted that they continued up to the ironstone 

 covering ; but a closer examination showed that above these 

 were clays, with well-preserved molluscan and coral forms similar 

 to those at the amphitheatre. Fossils were gathered up to a 

 height of 150 feet above the river, and the clay deposit is thus 

 about on a level with the upper limestones, or 40 feet higher than 

 the marls in Sec. X. There are about 20 feet of clays, and below 

 them succeed limestones almost to the level of the alluvial flat. 

 Change in the sediments, or, more probably, infiltration and 

 subsequent consolidation of the material, may account for the 

 limestone bands amongst the fossiliferous marls and clays of 

 these sections. 



Allusion has been made to the horizontal disposition of the 

 strata at one or two sections. This is very clearly seen on the 

 banks of Henderson's Flat at Sec. IX., and thence on to a little 

 beyond Sec. X. In the latter locality, the amphitheatre 

 encloses an angle of about 100 degrees, and on both of its sides 

 the limestone bands, as tested by the clinometer, appeared hori- 

 zontal ; the observations were made on the summit of Dog 

 Island, from which a good view of the amphitheatre is obtained. 



At the two outcrops last described basaltic rocks are entirely 

 wanting. It is important to note this, because just below 

 Henderson's Flat, and thus quite close at hand, there is, at a 

 comparatively low level on both sides of the river banks, a fringe 

 of basalt, which has passed over eocene strata in two small 

 exposures, one on the east and the other on the west side of the 

 stream. This flow can be traced for some miles, and is quite 

 distinct from the elevated and more extensive one which covers 

 the table-land on the summit of the western bank. The lower 

 and much older flow, for such it really is, shows only for a short 

 distance on the eastern margin of the river, and thus, we think, 

 never invaded the marls and limestones of Sections IX. and X. 



This interesting lower flow will be discussed more fully later 

 on; just now the sediments covered by it in the two sections 

 mentioned are briefly noted. 



In that on the eastern bank (Sec. VIII.), where the gorge of 

 the river narrows at the termination of Henderson's Flat, a 



