CONTENTS. 



VOL. XIV. 



No. PAGE 



I. — The Extraction of Zymase by means of Liquid Air. (Preliminary 

 Note.) By Henry H. Dixon, so.d., f.r.s. ; and W. E. G. Atkins, 

 M.A., so.B., A.i.o. (May, 1913.) ..... 1 



II. — Osmotic Pressures in Plant-Organs. III. — The Osmotic Pressure 

 and Electrical Conductivity of Yeast, Beer, and Wort. By 

 Henry H. Dixon, sc.d., f.r.s. ; and W. R. G. Atkins, m.a., sg.b., 

 A.I.O. (May, 1913.) . . . . . .9 



III. — On the Buoyancy of the Seeds of some Britannic Plants. By 



R. Lloyd Praeger. (May, 1913.) . . . .13 



IV. — On a Violet Colouring-Matter and its production by a certain 



Bacterium. By W. J. Hartley, b.a. (July, 1913.) . . 63 



V. — The Effect of a Low Potential Electric Current on Photographic 

 Plates. By Rev. H. V. Gill, s.j., b.a. (Plates I. and II.) 

 (July, 1913.) ....... 74 



VI. — The Maritime and Marine Lichens of Howth. By Matilda C. 



Knowles. (Plates III.-IX. and Map.) (August, 1913.) . 79 



VII. — Oxydases and their Inhibitors in Plant Tissues. By W. R. G. 



Atkins, sc.b., a.i.o. (August, 1913.) .... 144 



VIII. — Oxydases and their Inhibitors in Plant Tissues. Part II.— The 

 Flowers and Leaves of Iris. By W. E. G. Atkins, so.b., a.i.o. 

 (January, 1914.) . . . . . . .157 



IX. — Ginkgophyllum kiltorkense sp. nov. By T. Johnson, d.sc, f.l.s. 



(Plates X-XII.) (February, 1914.) . . . .169 



X. — Further Observations on Phytophthora erythroseptica Pethyb., and 

 on the Disease produced by it in the Potato Plant. By George 

 H. Pethybbidge, PH.D., B.so. (Plate XIII.) (January, 1914.) . 179 

 XI. — Oxydases and their Inhibitors in Plant Tissues. Part III : The 

 Localization of Oxydases and Catalase in some Marine Alga. 

 By W. R. G. Atkins, sc.b., a.i.o. (January, 1914.) 199 



