isohen divided in the Direction of 'their Avis. 



59 



Dutrochet applied the term " endosmosis " to the current 

 when established from within to without, and " exosmosis " 

 when from without to within. 



Having premised these remarks explanatory of the nature 

 of endosmosmic action, I shall proceed to apply them to the 

 explanation of the phenomena of divergence, commencing 

 with a very brief account of some experiments which I per- 

 formed with the hope of eliciting more information on this 

 point. 



1. A piece of the fresh stem of Lam turn album was divided 

 longitudinally, in the manner already described, to the extent 

 of three quarters of an inch : divergence immediately ensued, 

 the upper portions of the segments separating to half an inch. 



2. Another piece of a similar stem was treated in the same 

 manner, and its utmost extent of divergence ascertained. It 

 assumed the appearance shown in Jig. 8. It was then im- 



10 



LP 



mersed in distilled water : the divergence almost immediately 

 increased ; and in half an hour the segments had curved in 

 opposite directions, like the zodiacal sign of Aries {fig. 9.) 



3. The piece of stem used in the last experiment was 

 removed from the water, and plunged into a weak solution of 

 sugar : in the course of an hour the segments had lost their 

 curvature, and soon after their divergence, approaching so 

 closely as to touch each other, {fig. 10.) By replacing the piece 

 of stem in water, divergence again took place ; and so on 

 repeatedly. 



4. A young plant of Lamium album was placed in a vessel 

 containing water mixed with hydrocyanic acid, so that the roots 

 and lower part of the stem were immersed in the poisonous 

 mixture. In twenty-four hours the leaves appeared drooping, 

 and even yellowish at their tips, and the stem flaccid ; symp- 

 toms sufficiently indicative of the poisonous influence exerted 

 by the hydrocyanic acid on the plant. The upper part of 



v % 



