gg£) ON THE IRRITABILITY OF VEGETABLES. 



Mr. Whately The £rst mention of the co inaction of the leaves of the 

 contraction ' s P ecies of droserue, at least in this kn.gdom,wnen irritatea,wiU 

 when irritated, be found inWithering's Botany (vol. 2d p. 324) from which 

 it would appear, that Mr. Whately discovered this curious 

 phenomenon in August 1780. Mr. Gardom, who was with 

 Mr. Whately at the time, gives the following account of 

 This described, this contraction in a letter to Dr. Withering. " In August, 

 " 1780, examining th« drosera in company with Mr. 

 *.' Whately, on his inspecting some of the contracted leaves, 

 " we observed a small insect or fly very closely imprisoned 

 " therein, which occasioned some astonishment, to me at 

 " least, how it happened to get into that confined situation. 

 " Afterward, on Mr. Whately's centrically pressing with a 

 *' pin other leaves yet in their natural and expanded form, 

 " we observed a remarkable sadden and elastic spring of the 

 " leaves, so as to become inverted upwards, and as it were 

 *' incircling the pin, which evidently showed the method by 

 " which the fly came into its embarrassing situation. This 

 " experiment was renewed repeatedly, and with the same 

 ** effect, so that Mr. W r hately and myself are both certain 

 "of the fact." 

 Roth observed Roth published his work entitled Beitraege zur Botanick 

 it earlier. j n 1732, from which Dr. Withering translates the following 



remarks. " July 1779- Drosera rotuntlifolia and longifo- 

 His account of « }j a . I remarked, that many leaves were folded together 

 " from the point towards the base, and that all the hairs 

 *' were bent like a bow, but there was no apparent change 

 fi in the leaf stalk. Upon opening these leaves, I found in 

 '• each a dead insect. Hence I imagined, that this plant, 

 " which has some resemblance to the dioncea muscipula, 

 " might also have a similar moving power. W^ith a pair of 

 •* pliers I placed an ant upon the middle of a leaf of the 

 " drosera rotundifolia, but so as not to disturb the plant. 

 " The ant endeavoured to escape, but was held fast by the. 

 " clammy juice at the points of the hairs, which was drawn 

 « out by its feet into fine threads ; in some minutes the 

 « short hairs 01* the disk of the leaf began to bend, then 

 «' the long hairs, and laid themselves upon the insect. Af- 

 " ter a while the leaf began to bend, and in some hours the 

 '■« end of the leaf was so bent inwards as to touch the base. 



" The 



