2()8 ON THE IIUUtABtLITY OF VEGET ABLES. 



hours after the stimulus was applied, and yet in the course 

 of a few more hours both have contracted completely. The 

 last experiments were made within doors, and probably the 

 plants, though to appearance pretty fresh* were not in the 

 most irritable state. 

 Experiment Dr. Withering- mentions, that Mr.Whately's experiment 



wS^tog: Dr ** falled In his hailds ' and from Roth ' S and the ab0Ve obser- 

 probably b e - vations we possibly may account for this. From what 



St Zlti ton Mr ' Gan]om has said > lie no doubt expected a sudden 

 enough. contraction of the leaf when irritated ; but not finding- this 



to happen, he probably concluded, that the plant was not 

 in good condition* and, from placing implicit faith in Mr. 

 Gardom's experiments, was not anxious to repeat them. 

 I do not mean by what I have said, to impute to Mr. 

 Gardom any inaccuracy in the relation of his experiments, 

 but merely to put others on their guard, who wish to make 

 experiments on this plant. From what I have said it is 

 evident, that whoever has a wish to notice the motions of the 

 leaves of the droserae must not set out with the expectation 

 of seeing a rapid motion (similar to what happens in the 

 mimosa?) follow the application of a stimulus; but, to ob- 

 serve the ultimate effects, must watch with an attentive 

 eye for at least, in general, 20 minutes. It is then that he 

 will behold the bending of the hairs, which will soon be ac- 

 companied with that of the leaf. 

 Marnier in Having now considered the motions of the leaves of these 



which tiic con- plants, let us examine the manner in which they are ac- 

 counted for counted for. Broussonnet, in a memoir of the Academy of 

 Sciences of Paris for 1784, suspects, that the disengage- 

 ment of some fluids influences these motions. As Brou- 

 sonnet's theory is quoted by Sennebier, I shall translate the 

 words of the latter. After speaking of the dioncea musci- 

 byBrousonet l )U 'a, ne sa }' s : " ^ e (Brouseonuet) remarked the same 

 " phenomena upon two species of the drosera; their leaves 

 " at fir^t being folded upon themselves, their juices are not 

 " carried immediately towards the little hairs which cover 

 ** them, but after their developement we can perceive a 

 " drop of fluid towards the extremity of each hair; the in- 

 " sect absorbing this fluid, empties the vessels of the leaf, 

 ♦•' which folds upon itfelf, and resumes its former position : 



" the 



