466 



BOTANICAL GAZETTE 



[DECEMBER 



TABLE I 



ADDITION OF IRON, ZINC, COBALT, AND URANIUM 

 SFFER SOLUTION (STRAIN W, 1 2) * 



FeP0 4 /flask 



Zn/liter 



omg 

 1 



5... 

 20. . . 



50... 



Zn/liter 



o. 1 mg 



0.5. .. 

 1 



10 

 20 



50 



Co (N0 3 ) a /flask 



0.1 mg 



o.5> 

 1 . . 



10. . 



20. . 



50 



UOa(X0 3 ),/flask 



o. 1 mg 

 1 



5 

 10 



20 

 50 



ZnS04-j-7H 2 



O.026 



O.060 



O.061 



(0.267) 



(0.362) 



3-4 

 3-4 

 3-4 



2-3 

 2-3 



Fair 

 Fair 

 Fair 



Good^ 

 Practically sterile 



1. o mg. FePOVflask+zincf 



0.377 

 O.771 



O.694 



O.688 



O.723 



0-759 





2-3 

 1-2 



1-2 



1-2 

 1-2 

 1-2 



Good 



Fair 



Fair 



Fair 



Fair 



Fair 



1. o mg. FePOVflask+Co (N0 3 ) 2 



0.072 

 O.058 



0.049 

 0.026 



Practically 

 Practically 

 Practically 

 Practically 

 Practically 

 Practically 



sterile 

 sterile 

 sterile 

 sterile 

 sterile 

 sterile 



1. o mg. FeP04/flask+U02(NOa)j 



O.048 

 0.062 

 O.062 



O.058 

 O.069 



O.080 



Practically 

 Practically 

 Practically 

 Practically 

 Practically 

 Practically 



sterile 

 sterile 

 sterile 

 sterile 

 sterile 

 sterile 



CaCO^anVEkV^Sit-NH 3 ^ 63 ^^tU'^Vl KmP °^ ZuSO.+7lW>; and 

 compounds were the lahffin? NHlN ° 3 ' MgSO.+7ttO and "highest purity" sucrose. All other 



t The zinc (ZnSO.+ 7 H*» was added to these cultures 3.5 days after inoculation. 







