53 



The harvested seeds were grown again in the same way.^ Of twenty 

 seeds of the plants grown in beryllium solution, however, only seven 

 germinated and only three of the plants produced seeds, the resulting 

 crop of fourteen seeds weighing only 0.37 gram and averaging only 

 0.026 gram. This clearly shows that beryllium can not replace mag- 

 nesium in wheat, and very probably also not in any other of the Phaner- 

 ogams. The fact that the first generation yielded a much better result 

 than the second must be ascribed to the i^resence of a relatively large 

 amount of magnesium phosphate in the seeds used. 



In an experiment made by the writer with shoots of Tradescantia 

 placed in culture solutions containing 0.1 per cent beryllium sulphate 

 in one case and 0.1 per cent magnesium sulphate iii the other, the lower 

 leaves of the beryllium plant commenced to die after several weeks, 

 and the newly developed upper leaves scarcely reached one-third the 

 normal size, these shoots dying off after eight weeks, while in the con- 

 trol case they were still in a healthy condition.^ 



In regard to alga3, the writer has observed that a solution of beryl- 

 lium sulphate in which the other mineral nutrients are wanting exer- 

 cises an injurious influence sooner than does the magnesium sulphate. 

 Some threads of ISpirogyra communis were placed in 0.2 per cent of these 

 salts dissolved in purest distilled water, and it was found that the 

 number of dead and injured cells was much larger after two days in 

 the former case than in the latter.^ 



In a subsequent experiment the amount of both these sulphates was 

 diminished and mineral nutrients added, the composition of the main 

 solution being — 



Per mille. 



Calcium nitrate 0. 10 



Calcium sulphate .01 



Monopotassium phosphate 01 



Dipotassium phosphate 01 



Beryllium sulphate 10 



In this solution iSpirogyra threads were still normal and healthy after 

 three weeks, but had not grown to any noticeable extent. 

 In another experiment the following solution was prepared: 



Per luille. 



Calcium nitrate 0. 25 



Calcium sulphate 10 



Monopotassium carbonate 1. 00 



Monopotassium phosphate 05 



Ferrous sulphate Trace. 



One half of this solution received 0.2 gram magnesium sulphate and. 

 the other half 0.2 gram beryllium sulphate. Very soon a slight turbid- 

 ity, followed later by a flocculent precipitate, was noticed in the beryl- 



' The ash of the beryllium plants contained 2 per cent of BeO. 

 2 Mineral nutrients are stored up in the nodes, as already mentioned. 

 •"^For further information relative to the noxious effect of magnesium salts in 

 absence of calcium see p. 42. 



