BY R. M. JOHNSTON, F.LS. 123 
to have ascended into the névé at the time of a glacial epoch 
that we can reasonably hope to find good evidence of former 
glaciation due to local glaciers, and there only tn the higher 
valleys. As this region, however, corresponds to the southern 
extremity of Europe and the northerly extremity of Africa, 
it is probable that during a period of lowered temperature 
there would be a greatly increased rainfall, with a great in- 
crease in the dynamic effects of existing rivers and water- 
courses, both in highlands and lowlands. 
Such was the condition of similar latitudes during the ice 
age of Europe, according to Prof. James Geikie ; for in the 
same address, from which [ have so largely quoted, he states,* 
‘that in the extreme south of Europe, and in North Africa 
and West Asia, increased rain precipitation accompanied 
lowering of temperature ; from which it may be inferred that 
precipitation in glacial times was greater generally than it is 
now.” 
_ Now it is important to observe that in New South Wales, 
South Australia, Victoria, New Zealand, and Tasmania we 
have abundant evidence, in the extensive, irregular, coarse, 
shingly terrace-drifts formed in the main valleys frequently 
overlying our older tertiary basalts, of conditions which 
indicate, clearly, that during the period extending throughout 
the Neogene (Pliocene) and Pleistocene ages there was a 
ereatly increased rainfall; and so generally throughout these 
colonies are these characteristics manifested during this 
period that Australian geologists have long been in the habit 
of referring to it as the “ pluvial epoch” of Australasia. The 
representative geologists in Australasia are almost unanimous 
in placing the beginning of our glacier and pluvial epochs as 
far back as the commencement of the Pliocene age, and it 
would appear that this refrigerated pluvial epoch was either 
continuous or recurred again and again, well up to the close 
of the Pleistocene period ; and only the later terrace drifts, 
therefore, may be said to be the isochrones of the glacial drifts 
of the ice age of the Northern Hemisphere. 
I have referred to the evidence of lowered temperature, 
local alpine glaciation, and greatly increased rainfall of the 
pluvial epoch very frequently in my larger work on ‘The 
Geology of Tasmania.” 
Thus, in commenting upon the climate of the Neogene 
period (Pliocene), I stated (p. 219), “ Mr. Wilkinson is of 
opinion that the great drift deposits left at different levels 
upon the sides of the valleys as they were deepened towards 
the close of the Neogene period indicate a much greater 
rainfall than at present, and this greater rainfall is inferred to 
be due to the greater extent of glaciation of portions of the | 
* Loe cit., p. 214 
