CONTENTS. 
PAGE I 
Arber, Agnes. — The Leaf Structure of the Iridaceae, considered in relation to the Phyllode 
Theory. With sixty-six Figures in the Text 301 
Boyle, C. — Studies in the Physiology of Parasitism. VI. Infection by Sclerotinia Liber- 
tiana. With Plate XIV . 337 
Mottier, David M. — On Certain Plastids, with Special Reference to the Protein Bodies 
of Zea, Ricinus, and Conopholis. With Plate XV . 349 j 
Gates, R. Ruggles, and Rees, E. M. — A Cytological Study of Pollen Development in 
Lactuca.- With Plates XVI-XIX . . ... . . V . . 365 l 
Dastur, Jehangir Fardunji. — Cytology of Tilletia Tritici, (Bjerk.) Wint. With | 
Plate XX and nine Figures in the Text ... 399 
Cutting, E. M. — Observations on Variations in the Flowers of Stachys sylvatica, Linn. 
With five Figures in the Text - . 409 
Browne, Isabel M.^ P. — A Fourth Contribution to our Knowledge of the Anatomy of the 
Cone and Fertile Stem of Equisetum. With Plate XXI and twelve Figures in the Text 427 . 
NOTES. . ' I 
Chandler, M. E. J. — Note on the Occurrence of Sequoia in the Headon Beds of 
Hordwell, Hants . . . 457 
Horne, Arthur S. — Phloem Necrosis (Brown Bast Disease) in Hevea brasiliensis . 457 
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