494 



G. N. CALKINS AND L. H. GREGORY 



F. Conjugations in the L series {diagram 6) 



The four lines from an ex-conjugant of a wild pair of December 

 13 were isolated in permanent cultures on December 17. Rich 

 cultures were made on January 7, and conjugation tests on Jan- 

 uary 19, January 23, 13 pairs being found in quadrant B, and 

 6 pairs in quadrant C. A second set of rich cultures started 



Diagram 6 



February 6 and tested for conjugations on February 8, 9th, 14th 

 and 17th failed to confirm the results of the first tests, yielding 

 no pairs in any quadrant. 



A third set of rich cultures was made March 15 with three 

 quadrants only, one, quadrant D, having died immediately after 

 the February test. Conjugation tests were made March 19, 22, 



