570 president's address. 



At Cape Liptrap and Turton's Creek are bands of volcanic and 

 calcareous sedimentary material. This is perhaps the first certain 

 evidence in Australia of contemporaneous volcanic action. The 

 Pre-Devonian volcanic ash beds of the Keid River in Queensland, 

 described by Mr. R. L. Jack, F.G.S.,"^ niay, however, be as old, if 

 not older. 



Taken in conjunction with the Lower Silurian rocks, these Upper 

 Silurian have a thickness, as already stated, in Victoria of 35,000 

 feet. The Lilydale limestone and Moonee Ponds strata have 

 yielded an abundant marine fossil fauna. The Echinodermata 

 are represented by at least three species of ophiuroid starfish and 

 two crinoids, and corals and trilobites ( Phacops, Lichas, Hoinalo- 

 notus, Bronteus, and Calymene, &g.) abound. The interesting 

 gastropod Tremanotus has lately been described from the Lilydale 

 limestone by the Rev. A. W. Ores well, M.A.f 



(2) In New South Wales, strata of Upper Silurian age are 

 typically developed at Yass, where they are upwards of 3000 feet 

 thick. They consist of sandstones, grits, conglomerates, olive- 

 brown and blackish clay shales, and limestones. The lower strata 

 of this series exhibit suncrack and ripple-mark very perfectly, as 

 described in my report, j 



The sun-cracks in these rocks afi'ord the first-known conclusive 

 proofs of the existence of land in the Australian region. The 

 pebble conglomerates of course imply a pre-existing land, so that 

 portion of New South \Yales must have been a land area, at least 

 as far north as Mudgee, before Upper Silurian time. Halysites 

 has been recorded from Bombala, from near Yass, from Welling- 

 ton, and from near Molong, some beautifully preserved specimens 

 having lately been obtained from the last-mentioned locality by 

 the Rev. J. Milne Curran. 



* Geology and Palseontology of Queensland and New Guinea, by K. L, 

 Jack, F.G.S., F.R.G.S., and R. Etheridge, Junr. Text, p. 19. Brisbane, 

 1892. 



+ Notes on the Lilydale Limestone, Proc. Roy. Soc. Victoria, p. 42, 

 pi. VIII. fig. 1. 



+ Annual Report, Department of Mines, 1882, p. 148. By authority. 

 Sydney. 



