Peculiar Effects of Barium, Strontium, and Cerium on Spirogyra

Abstract

1. The chloroplasts of certain species of Spirogyra contract away from the cell wall in a peculiar and characteristic fashion in solutions CeCl3, BaCl2, and SrCl2 (in the case of the smaller kind in the last 2 only). The effect is observed in dilutions as great as 0 00005 M CeCl3 (in the case of the larger species), and in 0.0001 M BaCl2. SrCl2 also produces this effect, but not at such great dilutions as CeCl3 and BaCl2. 2. In the smaller species of Spirogyra the effect of BaCl2 is inhibited when BaCl2 is mixed with CeCl3 or CeCl2 in proper proportions.