CONTENTS OF VOLUME XXV 



Xo. i. JUNE, 191. v 



KITE, G. L. The Relative Permeability of the Surface and In- 

 terior Portions of the Cytoplasm of Animal and Plant Cells. I 



WOODSEDALEK, J. E. Spermatogenesis of the Pig with Special 

 Reference to the Accessory Chromosomes. 



SAFIR. SHELLEY R. A New Eye Color Mutation in Drosophila 



and its Mode of Inheritance 47 



XEWMAX, H. H. Parthenogenetic Cleavage of the Armadillo 



Ovum 54 - 



Xo. 2. JULY, 1913. 



SHELFORD, VICTOR E. The Reactions of Certain Animals to 

 Gradients of Evaporating Power of Air. A Study in Experi- 

 mental Ecology 79 



COTT, GEORGE C. Some Effects on Fund id us of Changes in the 

 Density of the Surrounding Medium 121 



CHAMBERS, ROBERT, JR. The Spermatogenesis of a Daphnid, 



Simocephalus vetulus ' .'T 134 



Xo. 3. AUGUST, 1913. 



VESTAL, ARTHUR G. Local Distribution of Grasshoppers in 



Relation to Plant Associations 141 



CHILD, C. M. The Asexual Cycle of Planaria I'data in Relation 



to Senescence and Rejuvenescence 181 



HOLMES, S. J. Developmental Changes of Pieces of Frog Embryos 



Cultivated in Lymph 204 



BERRY, S. STILLMAN. Nematolampas, A Remarkable New 



Cephalopod from the South Pacific 208 



Xo. 4. SEPTEMBER, 1913. 



DUXGAY, NEIL S. A Study of the Effects of Injury upon the 



Fertilizing Power of Sperm ... 213 



MORSE, EDWARD S. Observations on Living Solenomya (velum 



and borealis) 261 



TASHIRO, SHIRO. A Chemical Sign of Life . . 282 



in 



