JO 



THE CAUSES OP FLUCTUATIONS IN TURGESCENCE 



entirely urn 

 experiments : 



fleeted. That this is the case is sh 



by the results of the followi 



r> 



Experiment I. 



A leaf of Cassia sumatrana was taken and its three d 



pai 



of 



pinnae, together with the corresponding portion of the raehis, were 



ly luted into a 



tube through a perforated and paraffined cork 



The leaf was now set with 



divided lower extremity in a vessel of 



and the entire apparatus 



the freshly 

 introduced 



into a large chloroform-chamber 



Three hours later the parts of the leaf which were 



exposed to the chloroform were quite flaccid, whilst the protected 



green and turgid. 



tube having: been taken off, it 



remained quite 



The leaf was now removed from the chloroform -chamber, and, the 



simple moist chamber. On the following day 



ained as bef 



with the raehis and 



expansion 



hil 



tl 



whole of 



the portion which had been protected rem 



pinnae quite green and the latter in a state of full 



the rest of the leaf was of a brownish olive colour and with the pinnae absolutely 



flaccid. 



Experiment II. — A mature leaf of Cassia sumatrana, with the four 



tal pairs of 



pinnae 



d the 



iponding porti 



of the raehis protected as in the previous 



periment, was set in a chloroform-chamber. At the close of 



the 



portions were of a dull olive gree 

 protected portions remained in the 

 the cl 



and the 



pinnae 



very limp 



exposed 

 hilst the 



ginal 



state. The leaf was now removed fr 



amber, the test tube being taken off, and was set in the open laboratory 



O 



n 



the following 



day the portions which had been exposed to the chlorofor 



wei 



of 



a dull brownish olive, whilst all those which had been protected 



quite 



fresh 



green, and 



gid 



In a check leaf, which had been set in the open laboratory witl 



out water at the same time as the previous one, the pinnae were all dry and extremely 



d 



rigidly depressed, so that it could not have been any condit 



of atmosph 



humidity which 

 of the other. 



d the persistent greenness and turgidity of the protected portion 



Experiment III— A leaf of Cassia sumatrana was taken, and the lower extremity 

 of the petiole was freshly divided subaqueously. Both the basal and the distal portions 



action of chloroform for 

 • with the base of the 



were now protected and the central portion was exposed to the 

 some time. It was then removed and set in a moist chambe 







petiole luted into a bottle of water 



On the following day the portion of the raehis 

 which had been exposed to the chloroform was of a brownish colour and studded with 



numerous drops of brown exudation, and the corresponding pinnae were brow 



moist 



and flaccid 



while the protected portions both basal and distal were quite green and 



turgid and showed no traces of exudation 



Experiment IV. 



A 



youn & 



was set in a bottle of water 



g green shoot of Cassia sumatrana bearing several leaves 



The submerged end of the axis 



so 



was now fresl 



luted 



as to present a fresh absorptive surface, and the mouth of the bottle 



The apparatus was next set for 



was 



then removed and 



short time in a chloroform-chambe 



sferred to a common hermetically closed one. Visible exud 



ilv cut, 

 arefully 

 and was 



of 



fluid presently occurred on the axis, rachises and petioles, and the pinnae first partially 

 assumed the normal nocturnal position and then became quite flaccid and olive-brown 



and then became quite flaccid and 



