347 
concerned, his remarks are perfectly true, but as regards the 
two latter there are difficulties in the way of their being 
adopted in Australasia. Professor Hutton again aptly observes 
(Geol. Mag., Feb., 1885, p. 60). “We can always speak 
of the ‘Paleozoic’ or the ‘Mesozoic’ rocks of a 
country with all the accuracy required when using such 
terms, while we cannot always du the same _ with 
sufficient accuracy when referring to rocks belonging 
to the shorter periods or epochs. For example,’ he goes on 
to say, “I can speak of the Mesozoic rocks of New 
Zealand because the term is wide and makes no pretension to 
accuracy, but I cannot speak of Jurassic cr Cretaceous rocks of 
New Zealand with any approach to accuracy, although our 
present immethodical nomenclature often compels me to 
do so.” 
These difficulties have also been pointed out by W. T. 
Blanford, F.R.S. (in “ Classification of Sedimentary Strata,” 
pp. 318-9, Geol Mag., July, 1884). He expressly states that, 
“so far as the Geology of India has been studied, it appears 
doubtful whether the sedimentary formations of that country 
can be accurately classified by means of the European sub- 
divisions. The difficulty, it is true, is partly due.to the 
paucity of fossils in Indian rocks, but partly also to the cir- 
eumstance that the breaks in the sequence do not correspond 
with those especially remarkable in Europe.’ He elsewhere 
remarks that the same objection applies to other parts of 
the world. 
If the stratigraphic breaks in India do not harmonise with 
those of Europe, what likelihood is there in finding corres- 
ponding breaks in the rocks of Australasia? I have, there- 
fore, advanced good reasons for the course adopted by me 
hereafter in refraining to refer local rocks to sub-divisions of 
the Mesozoic Period, and also for merging the Carboniferous 
and Permian locally into one group, in harmony with the 
known facts of stratigraphy. 
The Carboniferous System in Tasmania, as thus defined, 
is marked, stratigraphically and organically, in its lower 
limits by an important break, so far as its relation with the 
uppermost members of the clay-slates of Lower Paleozoic 
age can be ascertained. Whether the Upper Devonian of 
Europe can in Tasmania be separated from the continuous 
Upper Paleozoic rocks, and the Lower Devonian from the 
Upper Silurian slates is a matter which has yet to be decided. 
Mr. Gould considered that the soft clay-slates of Fingal 
immediately and unconformably overlying similar clay-slates, 
but presenting special characters, and similarly related to the 
lower members of the carboniferous marine beds above, were 
the highest members of the Lower Paleozoic rocks known to 
