136 The South Australian Naturalist. 
traces in lateral and terminal moraines, also glacier lakes, 
erratics, glaciated pavements, and polished rocks. 
In Tasmania and the !South Island of New Zealand there 
I'emain extensive traces of former glaciations. 
Many theories have been advanced to account for the 
climatic changes which have undoubtedly occurred. One 
theory attempts to account for changes by variations in the 
eccentricity of the earth’s orbit and in the inclination of the 
earth’s axis to the plane of its orbit. 
Other theories look to terrestrial changes to produce varia- 
tions in climate. Among these may be classed variations in 
the elevation of the land in the distribution of the land masses. 
Such variations would have very great effects on the atmos- 
pheric and oceanic circulations (winds, currents, &c.j, and 
consequently on climate generally. 
Variations in the composition of the atmosphere, especially 
in respect to the amount of dust, carbon dioxide, ozone, or 
water vapour present have also been suggested. 
Variations in the amount of heat received from tlie sun 
have been suggested as causes for great climatic variations. 
Much depends on further research into the nature and secpience 
of ad solar phenomena before this seemingly plausible hypo- 
thesis of climatic -^nriation can find full acceptance. 
South Australian Aquarium Society. — A meeting of the 
Society was held on April 29th, at which Mr. Kimber delivered 
a most interesting address dealing with the history of Wil- 
lunga, and with the fossils and marine specimens found in 
the vicinity. During a recent camp of some members at Port 
Willunga good specimens were collected, and many of these 
were exJiibited by the lecturer in illustration of his remarks. 
The syllabus for the current session is now printed, and 
the evening' fixtures for the next quarter are given below. 
Any members of the Field Naturalists’ Section inteix'sted in 
tin; subject matter are cordially invited to attend. 
June 3rd — Microscopic exhibits, Mr. J. W. Hoskiug. 
July 1st — Aquatic Life, Mr. Wm. Ham. 
Meetings are held at the rooms of Mr. J. W. Ilosking, 77 
Sydenham Road, Norwood, at 8 p.m. 
HhlRBERT M. HALE. 
EXCHANGES. 
“The Victoria]! Naturalist,’’ February and March num- 
bers. 
“The Queensland Naturalist,’’ December, 1923. 
“The Australian Naturalist’’ (N.S.W.), Api’il, 1924. 
