CONTENTS. 



SERIES B. VOL, XCII. 



No. Bi 642.— January 3, 1921, 



PAGE 



Studies in the Mechanism of Enzyme Action. I. — Egle of the Reaction of the 

 Medium in Fixing the Optimum Temperature of a Ferment. By Arthur 

 Compton, M.B., D.Sc, Mackinnon Student, British Medical Association 

 Scholar. Communicated by Prof. B. Moore, F.E.S 1 



The Effect of Certain Dietary Deficiencies on the Suprarenal Glands. By C. H. 

 Kellaway, Fullei'ton Student of the Royal Society. Communicated by 

 W. B. Hardy, Sec. R.S. (Plate 1) 6 



The Growth of Seedlings in Wind. By Leonard Hill, M.B., F.R.S. (Director of 

 the Department of Applied Physiology, National Institute for Medical 

 Research). (Plates 2 and 3) 28 



Reflex Times in the South African Clawed Fi'og. By "W. A. Jolly. Communicated 



by Prof. E. Sharpey Schafer, F.E.S 31 



Studies of Photo-synthesis in Marine Algte. — 1. Fixation of Carbon and Nitrogen 

 from Inorganic Sources in Sea Water. 2. Increase of Alkalinity of Sea Water 

 as a Measure of Photo-synthesis. By Benjamin Mooie, F.R.S., Edward 

 Whitley, M.A., and T. Arthur Webster 51 



No. B 643.— February 1, 1921. 



Studies on Synapsis. III. — The Nuclear Organisation of the Germ Cells in Ltbelhda 

 depressa. By Lancelot Hogben. Communicated by Prof. E. W. MacBride, 

 F.R.S. (Plates 4-7) 60 



Cellular Immunity : Observations on Natural and Acquired Immunity to Cobra 

 Venom. By J. A. Gunn and R. St. A. Heathcote. Communicated by Prof. 

 Sherrington, F.R.S 81 



The Effect of Thyroid-feeding and of Thyro-parathyroidectomy upon the Pituitrin 

 Content of the Posterior Lobe of the Pituitary, the Cerebro-spinal Fluid, and 

 Blood. By P. T. Herring. Communicated by Sir E. Sharpey Schafer, F.E.S. 102 



On the Myogram of the Flexor-reflex evoked by a Single Break-shock. By K. Sassa 



and C. S. Sherrington, Pres. R.S 108 



