CONTENTS OF VOLUME XXXIV. 



No. i. JANUARY, 1918. 



SUMNER, F. B., AND COLLINS, H. H. Autotomy of the Tail in 



Rodents I 



HARRIS, J. ARTHUR. The Interrelationship of the Number of Sta- 

 mens and Pistils in the Flowers of Ficaria 7 



JENSEN, ALBERT C. Some Observations on Artemia gracilis, the 



Brine Shrimp of Great Salt Lake 1 8 



LOEB, LEO. The Relations between the Interstitial Gland of the 

 Testicle, Seminiferous Tubules and the Secondary Sexual 

 Characters 33 



CHILD, C. M. Physiological Senescence in Hydromedusce 49 



No. 2. FEBRUARY, 1918. 



LILLIE, RALPH S. Heredity from the Physico- Chemical Point of 



I 'ieii' 65 



CRAIG, WALLACE. Appetites and Aversions as Constituents of 



Instincts 91 



KANDA, SAKYO. Further Studies on the Geotropism of Parame- 



ciitni caudatum 1 08 



LYON, E. P. Note on the Geotropism of Paramecium 120 



CHAMBERS, ROBERT. The Microvivisection Method 121 



No. 3. MARCH, 1918. 



TURNER, C. H. The Locomotions of Surface-feeding Caterpillars 



are not Tropisms 137 



MORSE, WITHROW. Factors Involved in the Atrophy of the Organs 



of the Larval Frog 149 



COHN, EDWIN, J. Studies in the Physiology of Spermatozoa. . . . 167 



No. 4. APRIL, 1918. 



WERBER, E. I. Critical Notes on the Present Status of the Lens- 

 Problem 219 



WHITING, P. W. Sex-Determination and Biology of a Parasitic 



Wasp, Hadrobarcon brevicornis (Wesmael) 250 



SCHULTZ, ADOLF H. Studies in the Sex-Ratio in Man 257 



iii 



