BY L. KEITH WARD, B.A., B.E. i^j 



The northern and north-western Hmits have not yet 

 been determined. The area is probably continuous with 

 that which has last been described (VIII.). 



There are quartzites interbedded with argillaceous 



schists at Cox's Bight. These have a strike between 



N.N.W. and N.W., and dip to the south-west at low 

 angles. 



Of Port Davey there is but little known, save that 

 the white quartzites of the port extend northwards 

 alons: the coast for some distance. 



VIII.— NOMENCLATURE AND CORRELATION. 



It is impossible to discuss the nomenclature of these 

 rocks without at the same time briefly discussing the 

 relationship which they bear to rocks of like age in 

 extra-Australian areas. 



In assigning an age to the strata which have been 

 deposited since the beginning of the Cambrian era, the 

 evidence of the fossils preserved in the rocks is the most 

 important. But with regard to the Pre-Cambrian no 

 such criteria are available. 



It is true that there are well-authenticated cases of 

 the existence of organic remains in beds which are 

 stratigraphicall}^ lower than those containing the typical 

 lower Cambrian fauna ; and it is also true that the 

 diversity of the Cambrian fauna presupposes a Pre- 

 Cambrian fauna. But all organic remains are ill-pre- 

 served in the Pre-Cambrian rocks, while in Tasmania 

 no such remains have yet been detected. 



On stratigraphical evidence we have come to the 

 conclusion that the Tasmanian rocks here discussed are 

 truly Pre-Cambrian. But the word " Pre-Cambrian " 

 cannot but be regarded as merely a temporary epithet, 

 to be replaced by one which will define the age more 

 exactly when our knowledge of these rocks has become 

 sufficiently advanced to ustify a refinement in classifica- 

 tion. 



For the word " Pre-Cambrian," used in its literal 

 sense to designate those rocks which are of greater an- 

 tiquity than the Cambrian, embraces several rock- 



