

APPENDICES. 



127 



excessive and I yet the primary pnlvini were excessively irritable owing to absence of solar stimulation 



n 



adherent 



Experiment TL.-Jnly 2Uh, 3-30 p.m. Bright but clouded: soil rrry moist; no rain during /fc rW 

 previous days; leaves all in maximal diurnal position, frith their primary p<i fa, horizontal, shghtly deprwd 

 or very slightly ^m^.-Amputation of the tip of a single pinna, or even of a single distal pinnule! 



succeeded by 



the entire leaf and including extreme (Impression of 



the primary petiole, whilst amputation of the entire distal portion of the loaf b,n*1h the point 

 of origin of the lower pair of pinna) gave rise to little, and, in some oases, to BO petiolar 



VHSion 



cot 



and was presently followed by extreme petiolar elevation, although it was atl,n.i.,l hj 



exudation on the cut surface. Here there was manifestly no direct relation between the nv/r.tv i 



A \ * # i • 1 * • * 



the initial injury and the occurrence of petiolar movement, but very clearly a direct relation 1 !v, ,n 



the latter and the amount of distal leverage. Had depreasi B of the primary petiole beon d. ad- ut 

 on active contraction of the protoplasts of the primary pulvinus incident on mulat neeted 



with the sudden propagation of stimulant fluctuations in proMure along the oouiae <f llabrr- 

 landt's " Reizleitende system," or originating in any other fashion, this could not have bosn the OM<>, 

 as maximal fluctuations in pressure and maximal injury would under such circumstances have inevitably 

 led to maximal in placa of minimal movement. But, as it is a purely physical process, tho tendci y to 

 petiolar depression originating in connection with the fall in turgesoence in the pulvinar pan n< ui . 

 incident on the escape of liquid from the cut surfaces although greater in cases wher- the en re 

 distal parts of the leaf were amputated than whore only the t ns of pinna or pinnules we.e toteohod, 

 was more or less discounted by the great coincident decrease in distal leverage; whil.-t tho mu. smaller 

 escape attending amputation of the tips of individual pinnae or pinnules, not b<-ing accompanied 

 by any appreciable diminution in distal leverage, Sufficed to induce extreme petiolar depTCSHOO 

 At 6-30 p.m. the leaves were in fully developed nocturnal position. Tho petioles which had been 

 deprived of pinnoo were now not nearly so highly elevat I as they w. re shortly subsequent to the 



operation, but were still more elevated than those 



hand 



indicating the effects of the loss in turgesoence in the pulvinar tissues incident on the cessation of I nr 

 stimulation, and on the other the minor degree of petiolar depression attending tl s when d •..[ 





in 



APPKXDIX 13. 



THE EATE OF TRANSPIRATION IN MIMOSA PUDICA AND THE EFFECTS FOLLOWING 



DISTURBANCES IN THE RELATION UETWEEN TEAXSPIRATOfiY LOSS AND 1 oT-SUl'i'I.Y 



OF WATER. 



The rapidity of ti anspiratory loss is so great 



<let aehed axes set 



in 



water, and with their bases subaqueously divided to provide a fresh absorptive surface, only very 

 imperfectly assume the diurnal position under the influence of light unless the degree of atmospheric 

 humidity be relatively high. The activity of transpiratory lo^s is also very clearly in Heated by the 

 results which attend very inconsiderable diminutions in the amount of root-supply as is demonstrated 

 by the results of the followiDg experiments: 



KNT 



I. — A pot-plant, the leaves of which were in maximal diurnal position, awl which 

 had to some extent rooted into the ground through the opening in the bottom of the pot, was care- 

 fully taken up without injury to the projecting roots and was then conveyed to the laboratory. 

 On arrival there the pinnules of all the leaves were in maximal nocturnal position, owing partly to the 

 agitation which the leaves had been subjected to during transfer. The pot was now placed over 

 a vessel of water so that the projecting roots were immersed, and the entire apparatus was set in 

 a sealed chamber. The pinnules rapidly assumed the maximal diurnal position. The pot was now 

 removed gently from the water-vessel and chamber and set on a table in the open laboratory and 

 the pinnules once more gradually passed into the nocturnal position. When they had fully done so, 

 the pot was anew placed over the water-vessel within the chamber, and within the course of twenty 

 minutes the pinnules were once more in maximal diurnal position. On a second removal from the 



Ask. Roy. Eor. Gard. Calcutta Vol. VI. 



