CONTENTS 
PAGE 
Campbell, Douglas H.— The Gametophyte and Embryo of Botrychium simplex, Hitch- 
cock. With Plate XVI and ten Figures in the Text 441 
Mason, T. G. — Growth and Abscission in Sea Island Cotton. With fourteen Figures in 
the Text . . 457 
Priestley, J. H., and Pearsall, W. H.— Growth Studies. III. A ‘ Volumometer * 
Method of measuring the Growth of Roots. With one Figure in the Text . . . 485 
Thoday, D. — On the Organization of Growth and Differentiation in the Stem of the Sun- 
flower. With Plate XVII and ten Figures in the Text 489 
Redfern, Gladys M. — On the Course of Absorption and the Position of Equilibrium in 
the Intake of Dyes by Discs of Plant Tissue. With eight Figures in the Text . .511 
SlNNOTT, E. W., and Bailey, I. W.— The Significance of the ‘ Foliar Ray ’ in the Evolu- 
tion of Herbaceous Angiosperms. With Plates XVIII and XIX and one Figure in 
the Text 523 
Woodburn, William Logan.— S permatogenesis in Asterella hernisphaerica, Beauv. 
With Plate XX . '. . . . . . . . . . . .535 
Fry, E. J. — Some Types of Endolithic Limestone Lichens. With Plate XXI and nine 
Figures in the Text 541 
Williams, Maud. — O n the Influence of Immersion in certain Electrolytes upon Cells of 
Saxifraga umbrosa. With three Figures in the Text . . . . . . 563 
NOTE. 
Dowson, W. J. — A New Method of Paraffin Infiltration . . . . . 577 
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