CAN STRONTIUM AND BARIUM REPLACE CALCIUM. 



75 



strontium was very much neutralized (?) by the presence of calci- 

 um-salt. This is the reason why Hasclhoff was led to erroneous 

 conclusion. 



B) WATER CULTURE. 



i) Phlox paniculata. (Polemoni.) 



Young plants of Phlox paniculata were cut off and put in 

 the following solutions : 



i) 3.28 g. Ca(N0 3 ) 2 in 1 litre of water 1. 12 g. CaO + 2.16 g. N 2 O s 



2) 4.23 g. Sr(N0 3 ) 2 „ 



3) 5.22 g. Ba(N0 3 ) 2 „ 



( 1.64 g. Ca(N0 8 ) 2 „ 



4) \ 

 (2.12 g. Sr(NO s ) 2 



5) 



1.64 g. Ca(NO s ) 

 2.61 g. Ba(N0 3 ) 2 



3'2 » 



.2.07 g. SrO + 2. 16 g. N 2 O s 



.3.06 g. BaO + 2.16 g. N 2 O s 



.0.56 g. CaO + 1 .08 g. N 2 O b 



..1.04 g. SrO +1.08 g. N 2 O s 



..0.56 g. CaO + 1.08 g. N 2 O b 



..1.53 g. BaO+i.o8g. N 2 0 5 



The experiment was commenced on the 19th April, and by 

 the 22nd Ba plants had already begun to show signs of suffering, 

 the upper soft part of the stems turning at first brownish black 

 and drying up, and the leaves could not flourish any longer, 

 becoming yellow or brownish black, and on the 24th nearly all 

 the leaves withered away. Sr plants fared somewhat better 

 than Ba plants, but on the 24th they began to show the same 

 signs as Ba plants, and no leaves remained alive until the 27th. 

 Ca plants were quite healthy and showed no signs of suffering 

 until the end of the experiment (1st May), on the contrary, many 

 new leaves appeared during the experiment. Ca-f-Sr and 

 Ca + Ba plants were far better than Sr or Ba plants. By the 

 24th they had shown only slight signs of suffering, many leaves 

 remaining alive until the 27th ; no new leaves, however, appeared, 

 and on the 29th nearly all leaves except a few on the top, were 

 dead. Nevertheless it is quite evident that the poisonous action 

 of strontium and barium salts was much neutralized by the pre- 

 sence of calcium salt. 



