488 
S. C. BROOKS 
in which the ordinates represent conductance (in ohms) and the ab- 
scissae the time which elapsed between placing the material in distilled 
water and the determination of the conductance. 
Table i. 
Diffusion of Salts from Tissue Leached in Distilled Water for a Period of Twenty- 
three Hours Previous to Treatment with the Salt Solutions 
nductance in Ohms X lo^ of Distilled Water in Contact with Tissues 
Previously Exposed 25 Min. to : 
Distilled Water 
NaCl 0.2271/ 
CaCl2 0.1771/ 
Ce2Cl6 o.osM 
Distilled Water 
15 
205 
320 
5 
30 
389 
351 
7 
60 
407 
350 • 
15 
90 
403 
350 
18 
180 
261 
In this experiment the differences of conductance are caused almost 
exclusively by the diffusion from the tissues of the salts with solutions 
of which they have been treated; the conductances are therefore 
closely proportional to the conductances of these solutions. The 
experiment shows that diffusion of the absorbed salt from the tissues 
is completed within thirty minutes, and the increase of conductance 
in the different solutions subsequent to this time may be attributed 
largely to exosmosis from the protoplasm. 
Results ' 
If strips of dandelion peduncle be immersed (after momentary 
rinsing) in distilled water there is a steady exosmosis of electrolytes, 
and the rate of this exosmosis decreases gradually and without sudden 
change during the duration of the experiment, a matter of from six to 
eight hours. Since the protoplasm is normally in equilibrium with a 
more or less concentrated solution permeating the intercellular sub- 
stance, the replacement of this solution by distilled water will neces- 
sarily lead to a disturbance of the equilibrium, and may, without caus- 
ing any marked change in the normal permeability of the protoplasm, 
lead to an abnormal diffusion of substances from the cell, or, in other 
words, to an abnormal exosmosis. A previous treatment of the 
tissue with an isotonic solution of sodium chloride has the effect of 
accelerating this exosmosis, which, on the other hand, is inhibited by 
an isotonic solution of calcium chloride. 
