PROCEEDINGS OF GEOLOGICAL SOCIETIES. 



31 



mountains and the black boulder-like igneous rock. 2. Then came the erup- 

 tions in the Tertiary period, the ashes of which form br-^s in the Tertiary rock. 

 3. Then the eruptions on the upheaval of the Tertiary cliffs : these appear as 

 cones above faults on the Tertiary beds and on the edges of cliffs. 4. Lastly 

 the eruptions that have broken through the Tertiary beds, and the lava-streams 

 of which follow the natural valleys of the country. The volcanic phenomena 

 were illustrated by maps and numerous sketches by the author. Some Ter- 

 tiary Terebratul(E, some few fossil plants, and some Cretaceous fossils {Inocera- 

 mus and Belemtiitella) accompanied this memoir. 



3. " On the Geology of a part of South Australia." By T. Burr, Esq. 

 Erom the Colonial Office. 1848. 



The lowlands about Adelaide on the west, and along the river Murray on 

 the east, consist of horizontal beds of limestone and calcareo-siliceous deposits, 

 yellowish and reddish in colour, full of marine fossils, and of the Tertiary age. 

 Sometimes gypsum and ferruginous sand replace the limestone. These plains 

 are arid, except where granite protrudes from the surface, presenting cavities 

 in which rain- water collects. The author observed a similar Tertiary forma- 

 tion on Yorke's Peninsula, at Port Lincohi, and to the S.E. to beyond Rivoli 

 Bay ; and it probably forms vast tracts in New South Wales and Western 

 Australia. None of these tertiary districts appear to exceed an elevation of 

 three hundred feet above the sea. 



In describing two volcanos in South Australia, Mount Gambler and Mount 

 Schauck, Mr. Burr remarked that, coming from the west or north-west at about 

 twenty miles from these hills a white coral-limestone (Bryozoan limestone), 

 Gontairimg flint or chert, takes the place of the limestones and calcareous 

 sandstones, with recent sand-formations, previously passed over. This 

 white limestone is remarkable for the numerous deep weU-like water-holes 

 in it, within about twelve miles of the volcanic mountains, and about east or 

 west of them. 



Mount Gambler has a height of nine hundred feet above the sea (six hun- 

 dred feet above the plain), and has three craters, lying nearly east and west, 

 and occupied with lakes of fresli -water. Mount Schauck, at a distance of 

 about nine miles, magnetic south, is circular, and has one large, and two 

 small lateral craters. 



The author next described the granite, gneiss, and slaty rocks along a sec- 

 tion extending from the River Murray and Kangaroo Bange, across Mount 

 Barker and Mount Lofty, towards Adelaide ; and noticed the mode of occur- 

 rence of the ores of copper, iron, lead, &c., in these rocks. Lastly he noticed 

 and explained the occurrence of calcified stems of trees, standing in the posi- 

 tion of their growth, in the sand-dunes in tiiC Gulf of St. Yincent, near 

 Adelaide. 



4. " On some Tertiary deposits in South Australia." By the Bev. Julian 

 Edmund Woods. Communicated by the President. 



The author, in the first place, described the geographical features of that 

 part of the colony of South Australia to which his observations refer. It lies 

 between the Biver Murray on the west, and the colony of Victoria on the east ; 

 and includes an area of one hundred and fifty-six miles long, north and south, 

 and seventy broad from east to west. Some trap-dykes and four volcanic 

 hiUs are almost the only interruptions to the horizontality of these plains, 

 which rise gradually from the sea, and are occupied by the Tertiary beds 

 to be noticed; they extend into Victoria for some seventy miles, as far as 

 Port Eairy. 



In some places on the plains a white compact unfossiliferous limestone lies 

 under the surface-soil ; and is sometimes thirty-feet thick. Under this is a 

 fossiliferous limestone. The passage between the two is gradual. This latter 



