ZO.SHZ 
.to ! 
CONTENTS. 
No. LXIX, January, 1904. 
PAGE 
Lawson, A. A. — The Gametophytes, Archegonia, Fertilization, and Embryo of Sequoia 
sempervirens. With Plates I-IV . . . . . . . . . 1 
Wager, H. — The Nucleolus and Nuclear Division in the Root-apex of Phaseolus. With 
Plate V 29 
Worsdell, W. C. — The Structure and Morphology of the e Ovule/ An Historical Sketch. 
With twenty-seven Figures in the Text . . . . . . .57 
Cavers, F. — On the Structure and Biology of Fegatella conica. With Plates VI and VII and 
five Figures in the Text 87 
Potter, M. C. — On the Occurrence of Cellulose in the Xylem of Woody Stems. With 
Plate VIII I2i 
Williams, J. Lloyd. —Studies in the Dictyotaceae. I. The Cytology of the Tetrasporangium 
and the Germinating Tetraspore. With Plates IX and X 141 
Benson, Miss M. — Telangium Scotti, a new Species of Telangium (Calymmatotheca) showing 
Structure. With Plate XI and a Figure in the Text 161 
NOTES. 
Hem§ley, W. Botting. — O n the Genus Corynocarpus, Forst. Supplementary Note . . 1 79 
Weiss, F. E. — The Vascular Supply of Stigmarian Rootlets. With a Figure in the Text . 180 
Ewart, A. J. — Root-pressure in Trees 181 
No. LXX, April, 1904. 
Williams, J. Lloyd. — Studies in the Dictyotaceae. II. The Cytology of the Gametophyte 
Generation. With Plates XII, XIII, and XIV . 183 
Bower, F. O. — Ophioglossum simplex, Ridley. With Plate XV ...... 205 
Parkin, J. — The Extra-floral Nectaries of Hevea brasiliensis, Miill.-Arg. (the Para Rubber 
Tree), an Example of Bud-Scales serving as Nectaries. With Plate XVI . . .217 
Church, A. H. — The Principles of Phyllotaxis. With seven Figures in the Text . . . 227 
Mottier, D. M. — The Development of the Spermatozoid in Chara. With Plate XVII . 245 
Weiss, F. E. — A Mycorhiza from the Lower Coal-Measures. With Plates XVIII and XIX 
and a Figure in the Text ........... 255 
Reed, H. S. — A Study of the Enzyme-secreting Cells in the Seedlings of Zea Mais and 
Phoenix dactylifera. With Plate XX 267 
Vines, S. H. — The Proteases of Plants 289 
NOTES. 
Massee, G. — On the Origin of Parasitism in Fungi . . . . . . . .319 
Salmon, E. S. — Cultural Experiments with ‘ Biologic Forms ’ of the Erysiphaceae . . . 320 
Oliver, F. W., and Scott, D. H. — On the Structure of the Palaeozoic Seed Lagenostoma 
Lomaxi, with a Statement of the Evidence upon which it is referred to Lyginodendron . 321 
