VARIATIONS IN THE PROGENY OF A SINGLE EX- 

 CONJUGANT OF PARAMECIUM CAUDATUM 



GARY N. CALKINS and LOUISE H. GREGORY 



Department of Zoology, Columbia University 



EIGHT DIAGRAM FIGURES 



CONTENTS 



1. Nature of the problem 468 



2. Experimental methods 469 



A. Permanent cultures 470 



B. Petri-dish cultures 470 



C. Vitality tests 471 



D. Conjugation tests 471 



3. Histories of the different series studied 473 



A. The J series 473 



B. The B series 475 



C. The E' series 475 



D. The G, H', L, M, Q and T' series 475 



E. The O and P series 475 



4. The relative vitality of pure lines 476 



5. Size variations in pure lines from an ex-conjugant 480 



6. Variations in conjugating power of pure lines 484 



A. Conjugations in the J series 486 



B. Conjugations in the B series 490 



C. Conjugations in the E' series 491 



D. Conjugations in the T' series • 492 



E. Conjugations in the H' series 493 



F. Conjugations in the L series 494 



in the Q series 495 



in the G series 495 



in the M series 496 



in the G' series 497 



K. Conjugations in the O and P series 497 



Notes on the conjugation tests 498 



A. So-called 'maturity' in cultures 498 



B. History of the Syracuse-dish tests 501 



467 



G. Conjugations 

 H. Conjugations 

 I. Conjugations 

 J. Conjugations 



