CONTENTS OF VOLUME XXIX 



No. i. JULY, 1915. 



NEWMAN, H. H. Heredity and Organic Symmetry in Armadillo 



Quadruplets I 



VAN CLEAVE, H. J. Factors Concerned in the Production of 



Mitosis in Organisms Displaying Cell Constancy 33 



WHITNEY, DAVID D. The Production of Males and Females 



Controlled by Food Conditions in the English Hydatina senta. 41 

 CALKINS, GARY N. Microt&niella clymenellce, a New Genus and 



New Species of Colonial Gregarines 46 



LOEB, JACQUES. The Blindness of the Cave Fauna and the 



Artificial Production of Blind Fish Embryos by Heterogeneous 



Hybridization and by Low Temperatures 50 



CHURCHILL, E. P., JR. The Absorption of Fat by Freshwater 



Mussels 68 



No. 2. AUGUST, 1915. 



BLAKESLEE, ALBERT F. Sexual Reactions between Hermaphro- 

 ditic and Dioecious Mucors 87 



LOEB, JACQUES. Reversible Activation and Incomplete Membrane 



Formation of the Unfertilized Eggs of the Sea Urchin 103 



ALLEN, GEORGE D. Reversibility of the Reactions of Planaria 



dorotocephala to a Current of Water ill 



CHAPIN, CATHARINE L. A Case~qf .Hermaphroditismin Spelerpes 



bilineatus 129 



WOODWARD, ALVALYN E. Note on the Nature and Source of 



" Purple X" 135 



UHLENHUTH, EDUARD. Are Function and Functional Stimulus 



Factors in Producing and Preserving Morphological Structure? 138 



No. 3. SEPTEMBER, 1915. 



HEILBRUN, L. V. Studies in Artificial Parthenogenesis 149 



GATES, R. RUGGLES. On Successive Duplicate Mutations 204 



No. 4. OCTOBER, 1915. 

 WELLS, MORRIS M. Reactions and Resistance of Fishes in their 



Natural Environment to Acidity, Alkalinity and Neutrality. . 221 



iii 



