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Art. XVI. — On some Tertiary Rocks at Portland Bay, By 

 Rev. Julian Edmund Woods,, Penola, South Australia. 



[Read before the Institute 26th October, 1S59.] 



In a paper read before the Institute last year I described the 

 tertiary formation at Guichen Bay. I have now to deal with 

 the same formation on a different part of the coast, seen in 

 connection with two others. At Portland Bay (the most 

 westerly port in the colony of Victoria) there is a remarkable 

 exception to the general character of Australian coast scenery. 

 Instead of the long ridges of sand, covered with scanty vege- 

 tation, and scattered salt-bush, the coast is bold, rising to 

 fine bluffs on the northern side of the bay. In the centre of 

 the port, and on the left of the town of Portland, there is a 

 high bluff, having very much the appearance of a chalk cliff. 

 It is capped by a thin stratum of shingle, and above this lies 

 red clay. On the north side and on the right of the town 

 there is a high cliff of red clay. This is the Flagstaff Hill, 

 and on its summit a lighthouse is in course of erection. A 

 little past this at a short distance from the road there are a 

 series of islets called the Lawrence Rocks. These are vol- 

 canic. Further on at a small distance is Cape Grant. Here 

 the cliffs are of quite a different character to those found in 

 the bay. They are based on a thick stratum of basalt ; and 

 above these to the thickness of about 100 feet, the formation 

 is the same as that described at Guichen Bay. This is a cal- 

 careous sandstone, which I shall, for convenience, term 

 " crag." These three localities contain the rocks forming the 

 subject of the present paper. To return to the white chalk 

 cliff in the middle of the bay. This is called Whalers' Bluff. 

 It is formed of a loose friable white limestone. This is the 

 lowest of the three formations, because it is capped by the 

 decomposed trap rock which. underlies the crag. It contains 

 few or no perfect fossils. All that we found were disposed in 

 their seams about a foot apart, much broken, as if borne from 

 a distance before being stratified, in what must have been a 

 white calcareous mud. There can be no doubt that this forms 

 a portion of the coralline strata found at Mount Gambier ; 

 and is a portion of an immense deposit extending over nearly 

 a third part of the continent of Australia. It is continuous 



