BY R. M. JOHNSTON, F.LS. 87 
occurred long anterior to that known as the glacial period of 
Europe. And it is not without significance as bearing upon 
this question, and also upon the disputed question as to 
whether the extreme effects of glaciation could, at any time, 
have been produced by astronomical causes alone (7.¢., without 
the concurrence of favouring geographical causes), to find that 
the highest eccentricity occurred, according to Croll, 850,000 
years ago, at which time the difference between the sun’s 
distance at aphelion and perthelion was thirteen and a half 
millions of miles, whereas during the last glacial period of 
Europe and North America in the Northern Hemisphere, the 
maximum difference was ten and a half millions of miles 
only—that is three million miles or 22°22 per cent. less. As 
from the nature of the distribution of land and water in the 
Southern Hemisphere, it is probable that geographical causes 
would not play so important a part in barring the intro- 
duction of warm equatorial currents from the hemisphere 
specially affected; it is also probable that the alteration in 
climate in the Southern Hemisphere would be almost purely 
the result of astronomical causes alone. If we admit this, we 
should seek for the cause of the milder glacier period of 
Australasia since the cretaceous age, at that point of time 
when the eccentricity of the earth’s orbit was at its highest, 
and that was about 850,000 years ago, or fully 550,000 years 
anterior to the time of the great glacial epoch of Europe in 
the pleistocene age. This happily corresponds very closely 
with estimates as to the period which closes the miocene age, 
at which time there is evidence that the glacier period of 
Australasia began to mark its effects on our rocks and upon 
the organic life associated with them. 
Evidence of Glacial Action in the Elevated Valleys of the 
Australian Alps.—In the year 1885 Dr. von Lendenfeld 
(Proc. Lin. Soc. of N. S. Wales, pp. 44-53) in a paper, en- 
titled ‘‘ The Glacial Period in Australia,” gives an account of 
glacial phenomena discovered by him in the ascent of Mount 
Kosciusko, the highest elevation of the Australian Alps 
(7,200 feet), situated in about south lat. 36° 40‘ long. 148° east, 
near the south-eastern border of N. 8. Wales. On the 
southern slope it is drained by the head waters of the Snowy 
River, while its northern slope is drained by the head waters 
of the River Murray. The marks of glaciation discovered by 
Dr. Tendenfeld occur principally in the Wilkinson Valley, at 
elevations nowhere below 5,800 feet above sea level. These 
consist entirely of smoothed and rounded surfaces, whose 
grooves and scratches are supposed to have been removed by 
weathering, but yielding, as Dr. Lendenfeld states, to an 
eye experienced in reading the signs of glacier action indu- 
bitable proof of having been originally polished and rounded 
