158 T. W. E. DAVID. 



as well as striae, in this respect resembling those of Bacchus 

 Marsh. The superficial markings, however, have I think a 

 somewhat older appearance than those of the Bacchus Marsh 

 boulders. The boulder reproduced in fig. 2, Plate 4, may be con- 

 sidered fairly typical of those in the Lochinvar Glacial beds. The 

 ripple-marks in the flaggy sandstones near the top of the glacial 

 beds show that shallow water conditions obtained at all events 

 towards the deposition of the last of this group of beds. 



No fossils, macroscopic or microscopic, have as yet been found 

 in these three hundred feet of glacial beds. It is only at the very 

 top of the beds that marine fossils, Spirifer and Eurydesma, have 

 been found. 



The height of the outcrop of these glacial beds above the sea is 

 about two hundred feet. Their geological horizon is no less than 

 approximately between 5,000 and 6,000 feet below that of the 

 Branxton erratic horizon. 



Mr. E. 0. Andrews, b.a., is of opinion that some of the four 

 hundred and forty feet of " Shales with erratics," as described on 

 the section below, might also be considered as glacial beds. He 

 states that he found striated pebbles in the paddocks where these 

 upper beds had been denuded. These striated pebbles were not, 

 however, in situ as were most of those found by us on the horizon 

 of the beds three hundred feet thick. No favourable section was 

 available for ascertaining whether or not a striated rock pavement 

 lay at the base of the glacial beds. 



Appended is a section showing the position of the glacial horizons 

 respectively at Branxton and Lochinvar with reference to the 

 Sydney Coal-field where it underlies the building of the Royal 

 Society. It must not be assumed, however, that these beds all 

 exist under Sydney, though there is a strong probability that at 

 all events the Upper Glacial horizon, (that of Branxton), and 

 even that of the Greta Coal Measures, would be met with under 

 Sydney : — 



