1912] BRIEFER ARTICLES 251 



to be presumed that this made any material difference with the amount 



of barium chloride in solution. Two liters of barium chloride solution 



were applied to each of the experimental plants daily. The 10 per cent 



solution was used from July 8 to July n, 1908, inclusive. On July 13, 



5.5 per cent solution of barium chloride was used. No more of the 



solution was applied, and on July 18 it was found that the plants treated 



with barium chloride solution had turned yellow and dried up, while 



those treated with water were still green and fresh. The grass which 



surrounded the trenches did not seem to be affected by the barium 



chloride solution. Both sets of plants w r ere dug and dried for chemical 

 analysis. 



Unfortunately the plants treated with w r ater were by mistake thrown 

 away, so that no analysis could be made. However, an analysis was 

 made of Aragallus Lamberti collected on the tract adjacent to the 

 fenced patch at about the time when this experiment was going on, and 

 this will serve as a basis of comparison, though not having the value 

 of an analysis of the control plants. The analyses were made by the 

 Bureau of Chemistry. The plants treated with barium chloride showed 

 ash 41 .08 per cent and barium 1 .32 per cent. The Aragallus Lamberti 

 collected in the area adjacent to the experimental plot showed ash 

 22 . 08 per cent and barium o . 106 per cent. 



EXPERIMENT NO. 2 



Inasmuch as it was shown that a 10 per cent solution of barium chlo- 

 ride w T as poisonous to A ragallus Lamberti, it was decided to use a very 

 much more dilute solution and to duplicate the preceding experiment, 

 using a o 1 per cent solution. 



In this experiment 9 plants were chosen for the barium chloride 

 treatment, and 9 similar plants for the control experiment with water, 

 sixteen liters of barium chloride solution were used daily on the experi- 

 mental plants, and 16 liters of water on the control plants, with the 

 exception of one day when 14 liters were used. This experiment was 

 carried on from August 4 to August 18, inclusive. During this time both 

 groups of plants continued healthy and showed no effect of the treat- 

 ment. On August 20 both sets of plants were dug up and dried for 

 analysis, these analyses, as in the other cases, being made by the Bureau 

 °f Chemistry. The plants treated with barium chloride showed ash 

 52.26 per cent and barium 0.20 per cent. The plants treated with 

 ^ater showed ash 22 .98 per cent and barium 0.0613 per cent. 



