140 



CP59IXOHA3I OX FLUCTUATIONS IN TURGESCENCE. 



PERIME.NT X.— AugU3t 20th, 1 A.M. 



IL 



fallen in the 



/ 



morning and 



>th toil an I air tc-re rery humid.— Amputation of tips of axes was merely followed by local exudation 



of liquid on the cut surface 



I 



Results folloioinfj mechanical disturbance or separation ft 



the axis. 



mnl 



Exi'Erimi nt XI— A pot-plant was introduced into a sealed moist chamber and exposed to diffused 

 rill Extreme elevation and expansion of the leaves occurred, and when the whole apparatus was 



leaves strongly, the only movements which occurred were confined 



lently 



to a oertaiu number of pinnules which were actually in contact with the walls of the chamber. 



Exp K.ut 



XII— Ju 



/> 



was drenched with moisture. 



A pot-plant was conveyed over a mile of rough road without the leaves showing any appreciable departure 

 from th^ir normal diurnal condition, in spite of the continuous, agitation to which they were exposed 



during the transit. 



Experiment XIII.— June 



XIV 



gust 



Condit 

 Then 



and during several previous days atmospheric humidity was 



exceBiite and rainfall 



« 



nine 



leaves, 



teriu 



ndant. A vigorous shoot was detached from a plant and conveyed over a mile 



i between the garden in which the plant grew and the laboratory. It bore 

 nal ones being still very young. In spite of the continuous agitation to 



which it was exposed en route, it reached the laboratory with the primary petioles of all the leaves 



either horizontal or only very slightly depressed, and all the pinnules, save one or two 

 les in almost maximal diurnal position. Even half an hour later the pinnules were only 

 partially elevated; but, on exposure to a gentle current of warm dry air, they rapidly assumed the 



save one 

 isolated o 



-developed nocturnal positioi 

 Experiment XV. — Septerab 



Almost continuous drenching rain 



fatten during the previous 



/< 



The sky was covered with cloud. Everything was drenched with moisture and the leaves 



were 



diurnal 



Separ 



of 



hoots from the plants to wh : ch they belonged was 



attended by no movements whatever in the leaves unless they were subjected to violent agitation. 



c. — Remits following the application of flame to the tips of terminal pinnules of distal pinnce, 



Experiment XVI. — A pot-plant was enclosed within a 



sealed moist chamber. 



After it had 

 remained within it for some time the cover of the chamber was several times momentarily partially 



displaced and an open flame applied to the tips of the terminal pinnules of one of the distal pinnse 



f f several leaves. The application was followed by the occurrence of slow movements, in some cases 



extending over the entire leaf, in others confined to the injured pinme. In no case was there any 



propngation of movement to any leaf but the injured one. When similar treatment was applied to 



the leaves of plants growing in the open air, complete movements in all cases occurred throughout 



the whole of the injured leaf, and action was invariably propagated to at least one other leaf, although 

 atmospheric humidity was at the time by no meaus low. 



ERIMENT X\ 



A plant was treated as in the previous experiment. Wh 



flame 



was 



terminal 



one of the lower leaves, slow and partial elevation 

 oceunvd in all the pinnules of all the pinnse, and was followed by depression of the primary petiole; 



hut there was no propagation of movement to any other leaves. When similar treatment 



was applied 



in 



occurred throughout the 

 the plant. 



Experiment XYIII 



a luted pot within a sealed sulphuric acid chamber, complete and rapid action 

 whole of the injured leaf and was propagated to all the other leaves on 



A pot-plant was placed in a sealed moist chamber. The leaves became 



expanded. After an interval of two hours and a half 



removed and flame was applied to the tips 

 Stow and partial action occurred thro 

 movement to any other leaves. When si 



cover was partially 



the injured leaf, but there was 



no propagat 



of 



treatment was applied to a plant which had been for 



