TABLE OF CONTENTS. 
PAGE 
Boas, J. H. A Description of Some Artificial 
Synthetic ana Reconstructed Gems 30 
Browne, Maurice A. Nitrogen in the Economy 
of Nature 12 
Cooke, W. E. History of the Perth Observatory . . 80 
Glauert, Ludwig. The Protozoic Rocks of the North 
of Western Australia 51 
Grasby, W. Catton. Summer Temperatures of the Soil 
in Relation to the Supply of 
Available Nitrogen in the 
Wheat Areas 9 
„ A Triumph of Mendelism in 
Wheat Breeding. Professor 
Biffin’s Work at Cambridge 
University 47 
Hay, J . G Bird Day. A Plea for the Protection of 
Birds 12 
,, ,, Some Geographical Errors and their 
Influence upon Exploration and 
Settlement 12 
,, „ The Federal Capital Site 30 
Maitland, A. Gibb. Relics of the Permo-Carboniferous 
Ice Age in Western Australia 12 
Pfister, G. A. The Causes of the Fertility of the 
Western Australian Semi-arid Wheat Lands .... 38 
Simpson, Edward S. The Rare Metals and their 
Distribution in Western 
Australia 83 
,, , Unusual Types of Petrifaction 
from Dandarragan 33 
Stoward, Dr. An Investigation into the Structure 
and Functions of the Skin of the Potato Tuber. . 57 
