168 



cannot parallel the sub-divisions of such formation with any- 

 thing approaching to absolute precision. Begarded as a 

 whoio, however, the Carboniferous formation of America is 

 the geological equivalent of the Carboniferous formation of 

 Europe." Of similar value are the utterances of W. T. 

 Blanford and Prof. Hutton. The former urges that in India 

 " the breaks in the sequence do not correspond with those 

 especially remarkable in Europe." The latter boldly affirming, 

 in respect of New Zealand, a truth which, in my opinion, is 

 equally applicable to Australia and Tasmania, viz., that " we 

 can always speak of the ' Palaeozoic ' or the ' Mesozoic ' 

 rocks of a country with all the accuracy required when using 

 such terms, while we cannot always do the same with suffi- 

 cient accuracy when referring to rocks belonging to the 

 shorter periods or epochs." 



I have on. a former occasion observed that Palaeontology 

 divorced from facts of local stratigraphy is most unsatisfac- 

 tory, for we have the authority of Huxley (" Lay Sermons," 

 p. 234) for the statement, " All that geology can prove is 

 local order of succession." The question of distribution from 

 one geographical centre to its antipodes is also complicated 

 by the tendency in later periods to au increase in number and 

 variability of species, involving a greater risk in the 

 increasing struggle for specific existence over wide areas. 

 This is plainly indicated by the fact that while the molluscs 

 of the Carboniferous period in Europe and Australasia have 

 at least 23 per cent, of the species in common, the molluscs of 

 the tertiary period in the same regions have not even one per 

 cent, of the species in common. 



Of course English geologists have not had this aspect of the 

 case pressed home so closely to them in apractical way, because 

 unlike Australian geologists they have not been hampered in 

 their schemes of local classification by dejiendence upon the 

 widely differing association with respect to the stratigraphy 

 and palaeontology of a far distant region. Had they to form 

 their sub-divisions of systems with dependence upon the 

 associations of Australasian stratigraphy and palaeontology 

 the difficulties of the matter would have at once become 

 apparent to them as it now appears to Australasian geo- 

 logists. 



With these facts and considerations before us I cannot 

 but express my strong conviction that it would be unwise to 

 accept the triple sub-division of Triassic, Jurassic, and 

 Cretaceous, for the Mesozoic rocks of Australia and Tasmania,, 

 as such triple sub-division does not in the remotest degree 

 harmonise with the local facts of either stratigraphy or 

 palaeontology. 



In Tasmania there is no break showing alternations of sea 



