Induced Variations in NaCl Content of Non- 255 
Halophytes. 
extraordinarily instructive days, days penetrated too by the gladdest 
spirit of comradeship, days which we shall always remember for 
their strong and beautiful impressions of the world of British 
vegetation. I can only conclude with the hope that the pleasure 
which the writer of these notes himself found in the experience 
may find its echo in the hearts of all our British guides. 
ON INDUCED VARIATIONS IN THE OSMOTIC 
PRESSURE AND SODIUM CHLORIDE CONTENT OF 
THE LEAVES OF NON-HALOPHYTES. 
By Francis J. Lewis, D.Sc. 
URING an investigation into the effect of spray containing 
sodium chloride on the leaves of non-halophytes which is 
still proceeding, a series of experiments were carried out on 
the increase in sodium chloride content and rise of the osmotic 
pressure in leaves immersed in sea-water and in sodium chloride 
solutions. 
Comparatively little attention has been given to this question 
during recent years. Lesage 1 experimenting with Lepidium 
sativum and Raphanus sativus found that sodium chloride entered 
the tissues of these plants with great readiness. Boodle 3 in des¬ 
cribing the anatomical changes induced in the leaves of the wall¬ 
flower by watering with salt solutions found that such leaves gave 
an increased sodium and chlorine content as compared with normal 
leaves. The chlorine was tested by nitrate of silver, and the 
sodium by a flame reaction, but no quantitative results are given. 
In the experiments described below all the leaves show con¬ 
siderable variations in weight during immersion and an increase in 
sodium chloride content at the end of the experiment. The osmotic 
pressure of the cell sap is also greater after immersion for twelve 
or twenty-seven hours in salt solutions than in fresh leaves on the 
same branch. 
1 Lesage, P. “ Le chlorure de sodium dans les plantes.” Comptes 
rendus, Tome 114, p. 143. 
2 Boodle, L. A. ,l Succulent leaves in the Wall-flower.” New 
Phytologist, Vol. Ill, p. 39. 
