CONTENTS. 
PAGE', 
Bews, J. W. — Some General Principles of Plant Distribution as illustrated by the South 
African Flora . . . . . . . 3: 
Thoday, M. G. — Anatomy of the Ovule and Seed in Gnetum Gnemon, with Notes on 
Gnetum funiculare. With Plate I and five Figures in the Text . . . . . --37 
Stopes, Marie Carmichael. — T he Missing Link in Osmundites. With Plate II and 
one Figure in the Text . . . . . . 55 
Cutting, E. M. — On the Pollination Mechanism of Incarvillea Delavayi, Franch. With 
three Figures in the Text 
Torrey, R. E. — Telephragmoxylon and the Origin of Wood Parenchyma. With Plate III 1 
and three Figures in the Text 73 
Cayley, Dorothy M. — Some Observations on the Life-history of Nectria galligena, 
Bres. With Plates IV and V . . 7c j 
Gregory, F. G. — Studies in the Energy Relations of Plants. I. The Increase in Area of 
Leaves and Leaf Surface of Cucumis sativus. With fifteen Figures in the Text . . 93 
Wormald, H. — On the Occurrence in Britain of the Ascigerous Stage of a ^ Brown Rot ’ 
Fungus. With Plates VI and VII 125 
NOTES. 
Walkden, H. — The Isolation of the Organism causing Crown Gall on Chrysanthemum 
frutescens in Britain 137 
Williamson, H. S.— A New Method of preparing Sections of Hard Vegetable 
Structures 139 
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