CONTENTS vii 



Moore, A. R., and Cole, W. H. The response of PopiUia 

 japonica to light and the Weber-Fechner law 331 



Brooks, Matilda Moldenhauer. Comparative studies on 

 respiration. XIV. Antagonistic action of lanthanum as 

 relation to respiration 337 



Harris, J. Arthur, Gortner, Ross Aiken, and Lawrence, 

 John V. On the differentiation of the leaf tissue fluids of 

 ligneous and herbaceous plants with respect to osmotic 

 concentration and electrical conductivity 343 



Uhlenhuth, Eduard. Experimental production of gigantism 



by feeding the anterior lobe of the hypophysis 347 



Hecht, Selig. Time and intensity in photosensory stimulation. 367 



Hecht, Selig. The relation between the wave-length of light 



and its effect on the photosensory process 375 



LoEB, Jacques. Ion series and the physical properties of pro- 

 teins. III. The action of salts in low concentration 391 



No. 4, March 20, 1921. 



OsTERHOUT, W. J. V. A theory of injury and recovery. II. Ex- 

 periments with mixtures 4I5 



Brody, Samuel. The rate of ovulation in the dotneslic fowl 



during the pullet year 43I 



Fenn, Wallace O. The phagocytosis of solid particles. I. 



Quartz 439 



Fenn, Wallace O. The phagocytosis of solid particles. II. 



Carbon 455 



Fox, H. Munro. An investigation into the cause of the spon- 

 taneous aggregation of flagellates and into the reactions of 

 flagellates to dissolved oxygen. Part 1 483 



Fox, H. Munroe. An investigation into the cause of the spon- 

 taneous aggregation of flagellates and into the reactions of 

 flagellates to dissolved oxygen. Part II 501 



Coulter, Calvin B. The equilibrium between hemolytic sensi- 

 tizer and red blood cells in relation to the hydrogen ion 

 concentration 5I3 



Bibb, Lewis B. Summation of dissimilar stimuli applied to 



leaflets of sensitive briar (Schrankia) 523 



