BY R. M. JOHNSTON, F.L.S. 185 



character, like their equivalents along the Lower Murray 

 in Australia, and most ])robabl3^ they form the southern 

 limits of the ancient l^ertiary sea which occupied the 

 greater part of the existing plains bordering the Great 

 Australian Bight, and extending over the lower levels of 

 South Australia and Victoria within the limits indicated in 

 preceding chapter (p. 217). The rocks generally are com- 

 posed of alternating bands of shelly limestones, calcareous 

 sandstones, coral rag, ferruginous, gritty, and pebbly bands, 

 replete with fossil shells, corals, foraminfers, echinoderms, 

 sharks' teeth, &c. Certain thin zones of a hard calcareous 

 character recur, invarial^ly showing- similar characteristic 

 fossils, notably, Cellepora Gamhierensis, Lovenia Forhesi, 

 Waldheimia grandis, W. Garribaldiana, Rhynchonella 

 squamosa. 



The sandstones are also replete with fossils, in the upper 

 beds of which the following are typical; viz. — Turritella 

 Warhurtonii (T. Woods), Pauojjea Agnewi (Ten.-^ oodi^), 

 Valuta Tatei (R. M. Johnston), V. liannafordi (MJ-Coy), 

 V . Weldii (T. Woods), V. aniicivgulata (M'Coy), Cyprcea 

 Archeri (T. Woods), C. platypygu (M'Coy). 



In the sandstones of the Upper or " Turritella zone " at 

 Table Cape, land plants occur, intermixed with the marine 

 shells, among which may be noted a species of Pteris (P. 

 Belli, Johnston) and (Sapotacites oligoneuris, Ettings.) 

 The latter form has also been found by the author in 

 lacustrine formations at Macquarie Harbour and Hobart, 

 and may be of much value hereafte)' in determining the 

 relative age and position of the isolated marine and lacus- 

 trine formations throughout the island. 



The lowermost bed at Table Cape is almost wholly 

 composed of the remains of Crassatella ohlonga (T. Woods,) 

 and rests upon the upturned edges of slates belonging to 

 Silurian age. At Cape Grim and Table Cape the whole 

 series are capped with bosses of nepheline basalt, similar 

 to the older basalts of Victoria ; and nowhere along the 

 Tasmanian coast does the marine group exceed 70 feet 

 in thickness. From the character of the molluscs and 

 the small percentage (jaoi exceeding 2 per cent.) of species 

 having living representatives, it is clear that the marine 

 beds of Tasmania must be placed at the base of the Palaeo- 

 gene group, equivalent to the early Eocene of other 

 countries. 



