Ixx 



3. "Description of a new Vitrina, from the Travertin Beds, Geilston." 

 A paper by Mr. T. Stephens, F.G.S., was read by the hon. secretary : — 

 "Notes on boring operations in search of coal in Tasmania." 



In the discussion which followed the reading of Mr. Stephens' paper, 

 Mr, R. M. Johnston stated that little value could be placed in conclusions 

 formed from the partial evidence of marine organisms only as regards the 

 position of the Southern and Eastern coal deposits of Tasmania, because 

 he had found a considerable percentage of the species of the marine 

 organisms common to the mudstone series immediately overlying the 

 Mersey coal measures, also common to the mudstone series which is now 

 being tested by the boring drill at the Cascade Brewery, and also 

 common to the Tasmanite beds on the Mersey. Among the fossils 

 common to these deposits are the well-known forms : — Spirifera Tasma- 

 niensis, Spirifera Darioinii, Productus hrachythycerus, Pterinea lata, 

 Sanquinolites Etheridgei, Pecten Fittoni, Pecten squamuiiferus, Pecten 

 Illaioarra, Pecten nov. sp., Pleurotomaria Morrisiana, Protoretepora avipla, 

 Stetiopora Tasmaniensis, and several others, and the list no doubt could 

 be greatly increased. If, therefore, it be allowed that the Mersey and 

 Southern and Eastern coal deposits represent different horizons, the evi- 

 dences from marine organisms, taken by themselves with our present 

 knowledge, are absolutely valueless, at any rate neutral. It is from an 

 examination of the plant remains, associated with the respective coal 

 measures, that we have any grounds for separating them into different 

 groups, as representing different periods. Thus the prevailing plant 

 remains of the coal measures of the Mersey, which are the equivalents of 

 the Stony Creek, Anvil Creek, and other coal seams in New South Wales, 

 are Glossopteris Broimuana ; equisetaceous stalks, broadly and flatly ribbed, 

 allied to the Indian genus Schizoneura ; a curious orbicular form allied to 

 Actinopteris ; and numerous impressions of a form closely allied to Noegger- 

 athiopsis media. On the other hand, the Midland, Southern, and Eastern 

 coal measures of Tasmania have generally as prevailing forms Pecopteris 

 Australis, P. odontopiteroides , Phyllotheca Hookeri, Phyllotheca ramosa, 

 Sphenopteris alata, Zeugophyllites elongatus, and Glossopteris linearis, and, 

 therefore, the beds may, without doubt, as already shown by Feistmantel, 

 Rev. W. B. Clarke, R. Etheridge, junr., and others, be regarded as the 

 equivalents of the upper coal measures of New South Wales. Regarded 

 from an evolutionist's point of view, Mr. Johnston stated that, with the 

 late Rev. W. B. Clarke, he found it very difficult to recognise any break, 

 stratagraphic, or organic, between the upper and lower mudstone series of 

 AustraUa, so far as the marine organisms of undoubted palaeozoic facies 

 gave any evidence. If these subdivisions were to be classed as upper 

 palseozoiCj and the upper coal measures, according to various authorities, 

 as permian, oolitic, dias, or mesozoic, the separation must be doubtful and 

 purely one of local convenience. Mr. Johnston observed that while, on 

 the whole, he fully agreed with Mr. Stephens' conclusions, he was not pre- 

 pared to concur with liim in regarding the sandy and calcareous fossil- 

 iferous rocks occurring in the neighbourhood of Hobart, and in other 

 localities in the South and East, xuholly as the equivalents of the lower 

 marine beds of New South Wales, for it was not only conceivable but, un- 

 fortunately, probable that the Southern marine beds of Tasmania were 

 formed in situations more remotely removed from the oscillation of the 

 land which produced the conditions favourable to the deposits of the lower 

 eoal measures in such places as the Don, Mersey, Stony Creek, and Anvil 

 Creek basins ; that while these carbonaceous deposits intercal eating and 

 interrupting the series of marine beds were being formed in situations 

 adjacent to the shores of the old palaeozoic main land, the marine areas, 

 more remote from the land, still continued to deposit their marine sedi- 

 ments with an uninterrupted chain of marine organic life ; and it is quite 

 conceivable, and, indeed, in harmony with existing evidence, that the 



