Effects of Guaiacol and Hexylresorcinol in the Presence of Barium and Calcium

Guaiacol was applied at two spots on the same cell of Nitella. At one spot it was dissolved in 0.01 M NaCl, at the other in 0.01 M CaCl(2) or BaCl(2). The effect was practically the same in all cases, i.e. a similar change of P.D. in a negative direction, involving a more or less complete loss of P.D. (depolarization). When hexylresorcinol was used in place of guaiacol the result was similar. That Ca(++) and Ba(++) do not inhibit the effect of these organic depolarizing substances may be due to a lack of penetration of Ca(++) and Ba(++). The organic substances penetrate more rapidly and their effect is chiefly on the inner protoplasmic surface which is the principal seat of the P.D.