140 CCN.MNOIIAM Oy PLÜCIL-AriONS IN TITRGESCENCE.
ExpEitiMESi' X.—August 20th, 1 a.m. nenou showen hid fulUn in the c i h w of the moniiiig and
both soil and lir loere i-er/, //««W.—Aiupiitafcioa of tips of axes was merely followed by local Gsudation
of liquid on tbe eat surface.
5,—Remits following m''chanical di^'iflance or separaiion from the axis.
E s p e r t m e n t XI.—A pot-plaat was introduced into a sealed moist cliaiiiber and exposed to diifused
of tbe leaves occurred, and wlien tlie whole nppai'atu;
strongly, the only movements whioli occurred were confined
actually in contact with the walls of the chamber.
7S falling heavihj niid ererijthing was drenchcd with mohture.~
igh road without the leaves showing any appreciable departure
siinliglit. EKtreme elevation and espimsi
violently shaken, so as to agitate the lea\
to a certain nnraber of pinnules which wi
Esi'EUImukt 511.—June lUlh. Ran
spite of the continuous, agitation to which
A pot-plaut was conveyed over a mile of
fi-ora their normal dinrnal condition,
during the transit.
ExrERiMERT X I I I . — J u n e 24th. Conditions and results as in the previous esperiruent.
ExPEUijrENT XIV.—August 3rd. Then and during scvoril praaotis dai/s nimospheric hiiinkUti/ tens
e.rcmire and rainfall abundant.—A vigorous shoot was detached from a plant and convoyed over a mile
of rough road intervening between tbe garden in whicli the plant grew and the laboratory. It bore
nine leaves, the two terminal ones being still very young. In spito of the continuous agitation to
which it was exposed cn route, it reached t!ie laboratory with the primary petioles of all the leaves
save one either horizontal or only very slightly depressed, aud all the pinnules, save one or two
isolated ones, 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
fully-developed nocturnal position.
E.kpeuimest XV.—September 24th, Alnmt eontinuous drcnching rain had falh'n during the previous
forty-eight hours. The sky was covered tciih cloud. Eoerything icas drenched with moisture and the leaves
icere in ma.timal diurnal ijosiijo».-Separation of shoots from the plants to which they belonged was
attended by no movements whatever in the leaves unless they were subjected to violent agitation.
e. Remits following the applicaiion of flame to the tips of terminal ¡nnmdes of distal pinnce.
E x p e r i m e n t XVT.—A pot-plant was enclosnd within a sealed moist chamber. After it had
remained within it for some time the cover of tho chamber was soverul times momentarily partially
displaced and an open flame applied to the tips of the terminal pinnules of one of the distal pinnra
of several leaves. The application was followed by the occurrence of slow movements, in some cases
extending over the entire leaf, in others conflned to the injured pinna. In no case was there any
jiropagation of movement to any leaf but the injured one. When similar treatment was applied to
tlie leaves of plants growing in the open air, complete movsraents in all cases occurred throughout
tbe whole of the injured leaf, and action was invariably propagated to at least one other leaf, aiihi>ugh
atmospheric humidity was at the time by no meaus low.
E.'iPEniMENT X V I I . — A plant was treated as in the previous experiment. When flame was
npplied to one or two of the terminal pinnules of one of the lower leaves, slow and partial elevation
r)ccurr-d in all the pinnules of all the pinna, and was followed by depression of the primary petiole;
but tliere was no propagation of movement to any other leaves. Wlien similar treatment was npplied
to the leaf of a plant in a luted pot within a sealed sulphuric acid chamber, complete and rapid action
occurred throughout the whole of the injured leaf and was propagated to all the other leaves on
the plant.
E x p e b i j i e n t X V I I I . — a pot-plant was placed in a sealed moist chamber. The leaves became
extremely elevated and expanded. After an interval of two hours and a half, tbe cover was partially
removed and flame was applied to the tips of the terminal pinnules of a distal pinna of ono of the leaves.
Slow and partial action occurred throughout tbe injured leaf, but there was no propagation of
movement to any other leaves. When similar treatment was applied to a plnut which had been for
APi'ENDICES. 141
some hours in a sulphuric acid chamber, rapid and complete action took plaoo throughout the injured
leaf and was propagatod to all tiie other leaves on tho single axis of which tho plant was composed.
Experiment XIX.—June 12th, Soil very moM, atmospheric humidity AtV/Zi.-The application of flame
to the terminal pinnules oí distal pinnro of leaves of plants growing in the open ground was followed
by very slow and imperfect elevation of the pinnules of all the pinnm, and by slow and incomplete
depression of the primary petiole. There was never any propagation of movement to any other leaf.
Expekiment XX.—June 9th. if(7i» was falling heavily and the soil teas saturated teiih moisture.—The
application of flame to terminal pinnules of distal pinnro was followed by slow and imperfect
elevation of all the pinnules of all the pinnte of the injured leaf, and, in the case of one leaf which
was heavily loaded with adherent drops of rain, by depression of tho primary petiole. No propagation
to any other leaf occurred.
Expbriment XXI.—Juno 15th. The shj was completely covered with cloud, and heavy falls of rain
were occumng at frequent intervals. The soil icas very moist.—The application of flame to the tips of
terminal pinnules was followed by very slow, incomplete elevation of the pinnules of all the pinnaa
aud very slow, incompleto depression of tho primary petiole of the injured leaf. No propagation of
movement to any other leaf occurred in any case.
E x p e r i m e s t XXII.—June 10th, 8 a.m. AtmoHpherie tewperaiwe 80-5''J'. EimidUy 92 per cent. The
morning ivaa cool and still. Eeavy rainfall had occurred Just before tho period of experiment. Thc-re was
hnlUant sunshine, hut the plants tcere not directly exposed to The appHcation of flame to the tips of
terminal pinnules of distal pinnce was followed by slow aud almost complete elevation of the pinnules
of the injured pinna, and by slow, imperfect action in the opposite distol pinna and in the proximal
pinna on tbe same side as the injured one. No action whatever occurred ii
the pinnules of tbe
remaining pinna or in the primary petiole, and there was no propagation of 3
to any other
leaf.
E x p e r i m e n t XXIIL—June 21st, 8 a.m. Atmospheric temperature Sl-S^J*. Humidity 91 per cent.
The sky ivas completely eovcred with cloud, but no rain had fallen during the night, and the leaves were
consequently dry.—The application of flame to the tips of terminal pinnules oí distal pinnro was followed
by complete action throughout the injured leaf, save in one case in whiob no action occutrod in the
l)roximal pinna of the opposite side of the leaf, and another in which the primary petiole did not
undergo any depression. No propagation of movement to any other leaves occurred.
Experiment XXIV.—June 23rd, 8 a.m. Atmospheric temperature ll'iPF. Humidity 97 per cent.
Rain had fallen eoniintttusly for some hours previous, and was still filling heavily. Everything icas drenched
ivitk moisture.—The application of flame to the tips of terminal pinnules to the extent of actually charring
them was followed by slow action of the pinnules, never extending over mote than three pinnw, and,
where the leaves were not heavily loaded with adherent drops of rain, usually unattended by any depiession
of the primary petiole. In no case was there any propagation of movement to any other leaf.
E x p e r i m e n t XXV.—June 26th, 8 a.m. Atmofpheric temperature, 81-5°jF". Eumidity 90 per cent. The
!eat<e^ were dry, hut the soil was drenched tcith jr.oitUtre. The morning tens bright, but there was an absence
of direct ifins/ii»«.—The application i)f flame to the tips of terminal pinnules of distal pinn® was followed
by slow but almost complete elevation of all the pinnules of the injured pinna, depression of the primary
petiole, partial action in the pinnules of the proximal pinna of the injured side and in those of the
opposite distal pinna. In one or two instances incomplete elevation also occurred in the pinnules of the
remaining pinna. In no instance was there any propagation of movement to any other leaf.
E x p e r m e n t XXVI.—June 29ih. 8 a.m. Atmospheric temperature Humidity Qi per cent.
Rain was falling heatíhj.—The application of flame to the tips of terminal pinnules was followed only by
very slow elevation of the pinnules of the injured pinna, ond by incomplete elevation in those of
the remaining ones. Depression of the primary petiole did not occur, and there was no propagation of
movement to any other leaf.
d.—EJccts of the application of heat to a point in the course of a mature axis.
Experiment XXVII.—July 20tb. 8 a.m. Atmospheric temperature 80-5''. Humidity 95 per cent.
Heavy rain had fallen all uight, and rain teas still falling. Ecerything was drenched with moisture.—The
Ann. Roy. Bot. Gard. Cai.cutta Vol. VI.