BIPARENTAL INHERITANCE AND THE QUESTION OF 

 SEXUALITY IN PARAMECIUM^ 



H. S. JENNINGS AND K. S. LASHLEY 



The Zoological Laboratory of The John Hopkins University 



TWO FIGURES 



CONTENTS 



PART I. By H. S. Jennings 394 



Introduction 394 



Method of analysis : formulae 394 



Analysis of the observed results 410 



Distribution of survivals and deaths among the members of pairs 410 



Miss Cull's experiments 410 



Calkins' experiments 415 



Experiments of the author 415 



Summary on the relation of the survivals and deaths to pairing 420 



Comparative rate of reproduction in the two members of pairs 422 



Method of analysis 422 



Miss Cull's experiment 423 



Experiments by the author 424 



Biparental inheritance? 428 



Analysis of the experimental results 428 



PART II. By H. S. Jennings and K. S. Lashley 433 



Experiment 16: 241 pairs of conjugants propagated separately for forty days 433 



Distribution of survivals and deaths among the members of pairs 436 



Comparative rate of reproduction in the members of pairs 439 



Experiment 17: 239 split pairs propagated separately for twenty days 443 



Survivals and deaths in the split jjairs 445 



Rate of mortality 445 



Distribution of survivals and deaths 447 



Summary 449 



Comparative rate of reproduction in the members of split pairs 450 



' The results in the present paper are based to a certain extent on an analysis 

 of data presented in the tables of the preceding paper, on The Effect of Conjuga- 

 tion in Paramecium (this Journal, vol. 14, 1913, page 279). To facilitate reference 

 to the tables in that paper and to avoid confusion, the tables in the present contri- 

 bution are numbered consecutively with those of the former paper, beginning thus 

 with table 36. All references to tables numbered below 36 are therefore to those 

 in the preceding paper. 



393 



