PROCEEDINGS 



OF 



THE ROYAL SOCIETY. 



Series B. Vol. 87. No. B 594. 



BIOLOGICAL SCIENCES. 



CONTENTS. P, ge 



Negative After-images and Successive Contrast with Pure Spectral Colours. 

 By A. W. PORTER, B.Sc. F.R.S., Fellow of University of London 

 University College, and F. W. EDRIDGE-GREEN. M.D.. F.R.C.S. . . IQO 



The Ratio between Spindle Lengths in the Spermatocyte Metaphases of 



Helix pomatia. By C. F. U. MEEK. M.Sc, F.L.S., F.Z.S. (Plate 12) . 192 



Neuro-Muscular Structures in the Heart. By A. F. STANLEY KENT. M.A. 



Oxod., Professor of Physiology, University of Bristol . . . .198 



The Alleged Excretion of Creatine in Carbohydrate Starvation. By 

 GEORGE GRAHAM, Beit Memorial Fellow, and E. P. POULTON, 

 Radchffe Travelling Fellow ........ 205 



On Medullosa pusilla. By D. H. SCOTT, LL.D., D.Sc, For. Sec. R.S. 



(Plate 13) 221 



The Origin and Destiny of Cholesterol in the Animal Organism. Part XI. — 

 The Cholesterol Content of Growing Chickens under Different Diets. 

 By J. A. GARDNER and P. E. LANDER, Lindley Student of the 

 University of London ......... 229 



Contributions to the Biochemistry of Growth. — On the Lipoids of Trans- 

 plantable Tumours of the Mouse and the Rat. By W. E. BULLOCK and 

 W.CRAMER 236 



Studies in Heredity. II. — Further Experiments in Crossing British Species 



of Sea-urchins. By E. W. MacBRIDE^F.R.S 240 



The Optimum Temperature of Salicin Hydrolysis by Enzyme Action is 

 Independent of the Concentrations of Substrate and Enzyme. By 

 ARTHUR COMPTON, B.A., M.B., R.U.I., Imperial Cancer Research Fund 245 



printed for THE ROYAL SOCIETY and sold by 



HARRISON & SONS, 45, ST. MARTIN'S LANE. LONDON, W.C. 



Price Three Shillings. 



No. B 594. 



January 1, 1914. 



