CHARLESDARWINTOJ。D。HOOKER。
Down，June10[1864]……IhavenowreadtwoGermanbooks，andallIbelievethathasbeenwrittenonclimbers，andithasstirredmeuptofindthatIhaveagooddealofnewmatter。Itisstrange，butIreallythinknoonehasexplainedsimpletwiningplants。Thesebookshavestirredmeup，andmademewishforplantsspecifiedinthem。Ishallbeverygladofthoseyoumention。
IhavewrittentoVeitchforyoungNepenthesandVanilla（whichIbelievewillturnoutagrandcase，thougharootcreeper），ifIcannotbuyyoungVanillaIwillaskyou。Ihaveorderedaleaf—climbingfern，Lygodium。
Allthisworkaboutclimberswouldhurtmyconscience，didIthinkIcoulddoharderwork。（Hewasmuchoutofhealthatthistime。）
[Hecontinuedhisobservationsonclimbingplantsduringtheprolongedillnessfromwhichhesufferedintheautumnof1863，andinthefollowingspring。HewrotetoSirJ。D。Hooker，apparentlyinMarch1864:——
"ForseveraldaysIhavebeendecidedlybetter，andwhatIlaymuchstresson（whateverdoctorssay），mybrainfeelsfarstronger，andIhavelostmanydreadfulsensations。Thehot—houseissuchanamusementtome，andmyamusementIowetoyou，asmydelightistolookatthemanyoddleavesandplantsfromKew……TheonlyapproachtoworkwhichIcandoistolookattendrilsandclimbers，thisdoesnotdistressmyweakenedbrain。AskOlivertolookovertheenclosedqueries（anddoyoulook）andamuseabroken—downbrothernaturalistbyansweringanywhichhecan。Ifyoueverloungethroughyourhouses，remembermeandclimbingplants。"
OnOctober29，1864，hewrotetoDr。Gray:——
"Ihavenotbeenabletoresistdoingalittlemoreatyourgodchild，myclimbingpaper，orratherinsizelittlebook，whichbyJoveIwillhavecopiedout，elseIshallneverstop。Thishasbeennewsortofworkforme，andIhavebeenpleasedtofindwhatacapitalguideforobservationsafullconvictionofthechangeofspeciesis。"
OnJanuary19，1865，hewrotetoSirJ。D。Hooker:——
"Itisworkinghours，butIamtryingtotakeaday’sholiday，forI
finishedanddespatchedyesterdaymyclimbingpaper。ForthelasttendaysIhavedonenothingbutcorrectrefractorysentences，andIloathethewholesubject。"
AlettertoDr。Gray，April9，1865，hasawordortwoonthesubject:——
"Ihavebeguncorrectingproofsofmypaperon’ClimbingPlants。’I
supposeIshallbeabletosendyouacopyinfourorfiveweeks。Ithinkitcontainsagooddealnewandsomecuriouspoints，butitissofearfullylong，thatnoonewilleverreadit。If，however，youdonotSKIMthroughit，youwillbeanunnaturalparent，foritisyourchild。"
Dr。Graynotonlyreaditbutapprovedofit，tomyfather’sgreatsatisfaction，asthefollowingextractsshow:——
"IwasmuchpleasedtogetyourletterofJuly24th。NowthatIcandonothing，Imaunderoveroldsubjects，andyourapprobationofmyclimbingpapergivesmeVERYgreatsatisfaction。ImademyobservationswhenI
coulddonothingelseandmuchenjoyedit，butalwaysdoubtedwhethertheywereworthpublishing。IdemurtoitsnotbeingnecessarytoexplainindetailaboutthespiresinCAUGHTtendrilsrunninginoppositedirections;
forthefactforalongtimeconfoundedme，andIhavefounditdifficultenoughtoexplainthecausetotwoorthreepersons。"（August15，1865。）
"Ireceivedyesterdayyourarticle（IntheSeptembernumberof’Silliman’sJournal，’concludedintheJanuarynumber，1866。）onclimbers，andithaspleasedmeinanextraordinaryandevensillymanner。Youpaymeasuperbcompliment，andasIhavejustsaidtomywife，IthinkmyfriendsmustperceivethatIlikepraise，theygivemesuchheartydoses。Ialwaysadmireyourskillinreviewsorabstracts，andyouhavedonethisarticleexcellentlyandgiventhewholeessenceofmypaper……IhavehadaletterfromagoodZoologistinS。Brazil，F。Muller，whohasbeenstirreduptoobserveclimbersandgivesmesomecuriouscasesofBRANCH—climbers，inwhichbranchesareconvertedintotendrils，andthencontinuetogrowandthrowoutleavesandnewbranches，andthenlosetheirtendrilcharacter。"
（October1865。）
ThepaperonClimbingPlantswasrepublishedin1875，asaseparatebook。
Theauthorhadbeenunabletogivehiscustomaryamountofcaretothestyleoftheoriginalessay，owingtothefactthatitwaswrittenduringaperiodofcontinuedill—health，anditwasnowfoundtorequireagreatdealofalteration。HewrotetoSirJ。D。Hooker（March3，1875）:"Itisluckyforauthorsingeneralthattheydonotrequiresuchdreadfulworkinmerelylickingwhattheywriteintoshape。"AndtoMr。MurrayinSeptemberhewrote:"Thecorrectionsareheavyin’ClimbingPlants，’andyetI
deliberatelywentovertheMS。andoldsheetsthreetimes。"ThebookwaspublishedinSeptember1875，aneditionof1500copieswasstruckoff;theeditionsoldfairlywell，and500additionalcopieswereprintedinJuneofthefollowingyear。]
INSECTIVOROUSPLANTS。
[Inthesummerof1860hewasstayingatthehouseofhissister—in—law，MissWedgwood，inAshdownForest，whencehewrote（July29，1860），toSirJosephHooker;——
"LatterlyIhavedonenothinghere;butatfirstIamusedmyselfwithafewobservationsontheinsect—catchingpowerofDrosera;andImustconsultyousometimewhethermy’twaddle’isworthcommunicatingtotheLinneanSociety。"
InAugusthewrotetothesamefriend:——
"IwillgratefullysendmynotesonDroserawhencopiedbymycopier:thesubjectamusedmewhenIhadnothingtodo。"
Hehasdescribedinthe’Autobiography’（volumei。），thegeneralnatureoftheseearlyexperiments。Henoticedinsectsstickingtotheleaves，andfindingthatflies，etc。，placedontheadhesiveglandswereheldfastandembraced，hesuspectedthattheleaveswereadaptedtosupplynitrogenousfoodtotheplant。Hethereforetriedtheeffectontheleavesofvariousnitrogenousfluids——withresultswhich，asfarastheywent，verifiedhissurmise。InSeptember，1860，hewrotetoDr。Gray:——
"IhavebeeninfinitelyamusedbyworkingatDrosera:themovementsarereallycurious;andthemannerinwhichtheleavesdetectcertainnitrogenouscompoundsismarvellous。Youwilllaugh;butitis，atpresent，myfullbelief（afterendlessexperiments）thattheydetect（andmoveinconsequenceof）the1/2880partofasinglegrainofnitrateofammonia;butthemuriateandsulphateofammoniabothertheirchemicalskill，andtheycannotmakeanythingofthenitrogeninthesesalts！I
beganthisworkonDroserainrelationtoGRADATIONasthrowinglightonDionaea。"
LaterintheautumnhewasagainobligedtoleavehomeforEastbourne，wherehecontinuedhisworkonDrosera。Theworkwassonewtohimthathefoundhimselfindifficultiesinthepreparationofsolutions，andbecamepuzzledoverfluidandsolidounces，etc。etc。Toafriend，thelateMr。
E。Cresy，whocametohishelpinthematterofweightsandmeasures，hewrotegivinganaccountoftheexperiments。Theextract（November2，1860）
whichfollowsillustratesthealmostsuperstitiousprecautionsheoftenappliedtohisresearches:——
"GenerallyIhavescrutinisedeveryglandandhairontheleafbeforeexperimenting;butitoccurredtomethatImightinsomewayaffecttheleaf;thoughthisisalmostimpossible，asIscrutinisedwithequalcarethosethatIputintodistilledwater（thesamewaterbeingusedfordissolvingthecarbonateofammonia）。Ithencutofffourleaves（nottouchingthemwithmyfingers），andputtheminplainwater，andfourotherleavesintotheweaksolution，andafterleavingthemforanhourandahalf，Iexaminedeveryhaironalleightleaves;nochangeonthefourinwater;everyglandandhairaffectedinthoseinammonia。
"Ihadmeasuredthequantityofweaksolution，andIcountedtheglandswhichhadabsorbedtheammonia，andwereplainlyaffected;theresultconvincedmethateachglandcouldnothaveabsorbedmorethan1/64000or1/65000ofagrain。Ihavetriednumbersofotherexperimentsallpointingtothesameresult。Someexperimentsleadmetobelievethatverysensitiveleavesareactedonbymuchsmallerdoses。Reflecthowlittleammoniaaplantcangetgrowingonpoorsoil——yetitisnourished。Thereallysurprisingpartseemstomethattheeffectshouldbevisible，andnotunderveryhighpower;foraftertryingahighpower，Ithoughtitwouldbesafernottoconsideranyeffectwhichwasnotplainlyvisibleunderatwo—thirdsobjectglassandmiddleeye—piece。Theeffectwhichthecarbonateofammoniaproducesisthesegregationofthehomogeneousfluidinthecellsintoacloudofgranulesandcolourlessfluid;andsubsequentlythegranulescoalesceintolargermasses，andforhourshavetheoddestmovements——coalescing，dividing，coalescingadinfinitum。Idonotknowwhetheryouwillcarefortheseill—writtendetails;but，asyouasked，IamsureIamboundtocomply，afteralltheverykindandgreattroublewhichyouhavetaken。"
OnhisreturnhomehewrotetoSirJ。D。Hooker（November21，1860）:——
"IhavebeenworkinglikeamadmanatDrosera。Hereisafactforyouwhichiscertainasyoustandwhereyouare，thoughyouwon’tbelieveit，thatabitofhair1/78000ofonegraininweightplacedongland，willcauseONEofthegland—bearinghairsofDroseratocurveinwards，andwillaltertheconditionofthecontentsofeverycellinthefoot—stalkofthegland。"
AndafewdayslatertoLyell:——
"IwillandmustfinishmyDroseraMS。，whichwilltakemeaweek，for，atthepresentmoment，IcaremoreaboutDroserathantheoriginofallthespeciesintheworld。ButIwillnotpublishonDroseratillnextyear，forIamfrightenedandastoundedatmyresults。Ideclareitisacertainfact，thatoneorganissosensitivetotouch，thataweightseventy—eighttimeslessthanthat，viz。，1/1000ofagrain，whichwillmovethebestchemicalbalance，sufficestocauseaconspicuousmovement。Isitnotcuriousthataplantshouldbefarmoresensitivetothetouchthananynerveinthehumanbody？YetIamperfectlysurethatthisistrue。WhenIamonmyhobby—horse，Inevercanresisttellingmyfriendshowwellmyhobbygoes，soyoumustforgivetherider。"
Theworkwascontinued，asaholidaytask，atBournemouth，wherehestayedduringtheautumnof1862。Thediscussioninthefollowingletteron"nervousmatter"inDroseraisofinterestinrelationtorecentresearchesonthecontinuityofprotoplasmfromcelltocell:]
CHARLESDARWINTOJ。D。HOOKER。
CliffCottage，Bournemouth。
September26[1862]。
MydearHooker，Donotreadthistillyouhaveleisure。Ifthatblessedmomentevercomes，Ishouldbeverygladtohaveyouropiniononthesubjectofthisletter。
IamledtotheopinionthatDroseramusthavediffusedmatterinorganicconnection，closelyanalogoustothenervousmatterofanimals。Whentheglandsofoneofthepapillaeortentacles，initsnaturalpositionissuppliedwithnitrogenisedfluidandcertainotherstimulants，orwhenloadedwithanextremelyslightweight，orwhenstruckseveraltimeswithaneedle，thepedicelbendsnearitsbaseinunderoneminute。Thesevariedstimulantsareconveyeddownthepedicelbysomemeans;itcannotbevibration，fordropsoffluidputonquitequietlycausethemovement;itcannotbeabsorptionofthefluidfromcelltocell，forIcanseetherateofabsorption，whichthoughquick，isfarslower，andinDionaeathetransmissionisinstantaneous;analogyfromanimalswouldpointtotransmissionthroughnervousmatter。Reflectingontherapidpowerofabsorptionintheglands，theextremesensibilityofthewholeorgan，andtheconspicuousmovementcausedbyvariedstimulants，Ihavetriedanumberofsubstanceswhicharenotcausticorcorrosive，……butmostofwhichareknowntohavearemarkableactiononthenervousmatterofanimals。Youwillseetheresultsintheenclosedpaper。Asthenervousmatterofdifferentanimalsaredifferentlyactedonbythesamepoisons，onewouldnotexpectthesameactiononplantsandanimals;onlyifplantshavediffusednervousmatter，somedegreeofanalogousaction。Andthisispartiallythecase。Consideringtheseexperiments，togetherwiththepreviouslymaderemarksonthefunctionsoftheparts，Icannotavoidtheconclusion，thatDroserapossessesmatteratleastinsomedegreeanalogousinconstitutionandfunctiontonervousmatter。Nowdotellmewhatyouthink，asfarasyoucanjudgefrommyabstract;ofcoursemanymoreexperimentswouldhavetobetried;butinformeryearsItriedonthewholeleaf，insteadofonseparateglands，anumberofinnocuous（Thislineofinvestigationmadehimwishforinformationontheactionofpoisonsonplants;asinmanyothercasesheappliedtoProfessorOliver，andinreferencetotheresultwrotetoHooker:"PraythankOliverheartilyforhisheapofreferencesonpoisons。"）substances，suchassugar，gum，starch，etc。，andtheyproducednoeffect。Youropinionwillaidmeindecidingsomefutureyearingoingonwiththissubject。Ishouldnothavethoughtitworthattempting，butIhadnothingonearthtodo。
MydearHooker，Yoursverysincerely，CH。DARWIN。
P。S。——WereturnhomeonMonday28th。ThankHeaven！
[Alongbreaknowensuedinhisworkoninsectivorousplants，anditwasnottill1872thatthesubjectseriouslyoccupiedhimagain。ApassageinalettertoDr。AsaGray，writtenin1863or1864，shows，however，thatthequestionwasnotaltogetherabsentfromhismindintheinterim:——
"DependonityouareunjustonthemeritsofmybelovedDrosera;itisawonderfulplant，orratheramostsagaciousanimal。IwillstickupforDroseratothedayofmydeath。HeavenknowswhetherIshalleverpublishmypileofexperimentsonit。"
Henotesinhisdiarythatthelastproofofthe’ExpressionoftheEmotions’wasfinishedonAugust22，1872，andthathebegantoworkonDroseraonthefollowingday。]
CHARLESDARWINTOASAGRAY。
[Sevenoaks]，October22[1872]……IhaveworkedprettyhardforfourorfiveweeksonDrosera，andthenbrokedown;sothatwetookahousenearSevenoaksforthreeweeks（whereI
nowam）togetcompleterest。Ihaveverylittlepowerofworkingnow，andmustputofftherestoftheworkonDroseratillnextspring，asmyplantsaredying。Itisanendlesssubject，andImustcutitshort，andforthisreasonshallnotdomuchonDionaea。ThepointwhichhasinterestedmemostistracingtheNERVES！whichfollowthevascularbundles。Byaprickwithasharplancetatacertainpoint，Icanparalyseone—halftheleaf，sothatastimulustotheotherhalfcausesnomovement。Itisjustlikedividingthespinalmarrowofafrog:——nostimuluscanbesentfromthebrainoranteriorpartofthespinetothehindlegs;butiftheselatterarestimulated，theymovebyreflexaction。Ifindmyoldresultsabouttheastonishingsensitivenessofthenervoussystem（！？）ofDroseratovariousstimulantsfullyconfirmedandextended……
[HisworkondigestioninDroseraandotherpointsinthephysiologyoftheplantsoonledhimintoregionswherehisknowledgewasdefective，andheretheadviceandassistancewhichhereceivedfromDr。BurdonSandersonwasofmuchvalue:]
CHARLESDARWINTOJ。BURDONSANDERSON。
Down，July25，1873。
MydearDr。Sanderson，IshouldliketotellyoualittleaboutmyrecentworkwithDrosera，toshowthatIhaveprofitedbyyoursuggestions，andtoaskaquestionortwo。
1。ItisreallybeautifulhowquicklyandwellDroseraandDionaeadissolvelittlecubesofalbumenandgelatine。Ikeptthesamesizedcubesonwetmossforcomparison。WhenyouwerehereIforgotthatIhadtriedgelatine，butalbumenisfarbetterforwatchingitsdissolutionandabsorption。Franklandhastoldmehowtotestinaroughwayforpepsin;
andintheautumnhewilldiscoverwhatacidthedigestivejuicecontains。
2。Adecoctionofcabbage—leavesandgreenpeascausesasmuchinflectionasaninfusionofrawmeat;adecoctionofgrassislesspowerful。ThoughIhearthatthechemiststrytoprecipitateallalbumenfromtheextractofbelladonna，Ithinktheymustfail，astheextractcausesinflection，whereasanewlotofatropine，aswellasthevalerianate[ofatropine]，producenoeffect。
3。Ihavebeentryingagoodmanyexperimentswithheatedwater……Shouldyounotcallthefollowingcaseoneofheatrigor？Twoleaveswereheatedto130deg，andhadeverytentaclecloselyinflected;onewastakenoutandplacedincoldwater，anditre—expanded;theotherwasheatedto145deg，andhadnottheleastpowerofre—expansion。Isnotthislattercaseheatrigor？Ifyoucaninformme，Ishouldverymuchliketohearatwhattemperaturecold—bloodedandinvertebrateanimalsarekilled。
4。Imusttellyoumyfinalresult，ofwhichIamsure，[asto]thesensitivenessofDrosera。Imadeasolutionofonepartofphosphateofammoniabyweightto218，750ofwater;ofthissolutionIgavesomuchthataleafgot1/8000ofagrainofthephosphate。Ithencountedtheglands，andeachcouldhavegotonly1/1552000ofagrain;thisbeingabsorbedbytheglands，sufficedtocausethetentaclesbearingtheseglandstobendthroughanangleof180deg。Suchsensitivenessrequireshotweather，andcarefullyselectedyoungyetmatureleaves。Itstrikesmeasawonderfulfact。ImustaddthatItookeveryprecaution，bytryingnumerousleavesatthesametimeinthesolutionandinthesamewaterwhichwasusedformakingthesolution。
5。Ifyoucanpersuadeyourfriendtotrytheeffectsofcarbonateofammoniaontheaggregationofthewhitebloodcorpuscles，Ishouldverymuchliketoheartheresult。
Ihopethisletterwillnothaveweariedyou。
Believeme，yoursverysincerely，CHARLESDARWIN。
CHARLESDARWINTOW。THISELTONDYER。
Down，24[December1873？]。
MydearMr。Dyer，Ifearthatyouwillthinkmeagreatbore，butIcannotresisttellingyouthatIhavejustfoundoutthattheleavesofPinguiculapossessabeautifullyadaptedpowerofmovement。LastnightIputonarowoflittlefliesnearoneedgeoftwoYOUNGISHleaves;andafter14hourstheseedgesarebeautifullyfoldedoversoastoclasptheflies，thusbringingtheglandsintocontactwiththeuppersurfacesoftheflies，andtheyarenowsecretingcopiouslyaboveandbelowthefliesandnodoubtabsorbing。Theacidsecretionhasrundownthechannellededgeandhascollectedinthespoon—shapedextremity，wherenodoubttheglandsareabsorbingthedelicioussoup。Theleafononesidelooksjustlikethehelixofahumanear，ifyouweretostuffflieswithinthefold。Yoursmostsincerely，CH。DARWIN。
CHARLESDARWINTOASAGRAY。
Down，June3[1874]……IamnowhardatworkgettingmybookonDrosera&Co。readyfortheprinters，butitwilltakesometime，forIamalwaysfindingoutnewpointstoobserve。IthinkyouwillbeinterestedbymyobservationsonthedigestiveprocessinDrosera;thesecretioncontainsanacidoftheaceticseries，andsomefermentcloselyanalogousto，butnotidenticalwith，pepsin;forIhavebeenmakingalongseriesofcomparativetrials。
NohumanbeingwillbelievewhatIshallpublishaboutthesmallnessofthedosesofphosphateofammoniawhichact……IbeganreadingtheMadagascarsquib（Adescriptionofacarnivorousplantsupposedtosubsistonhumanbeings。）quitegravely，andwhenIfounditstatedthatFelisandBosinhabitedMadagascar，Ithoughtitwasafalsestory，anddidnotperceiveitwasahoaxtillIcametothewoman……
CHARLESDARWINTOF。C。DONDERS。（ProfessorDonders，thewell—knownphysiologistofUtrecht。）
Down，July7，1874。
MydearProfessorDonders，MysonGeorgewritestomethathehasseenyou，andthatyouhavebeenverykindtohim，forwhichIreturntoyoumycordialthanks。Hetellsmeonyourauthority，ofafactwhichinterestsmeinthehighestdegree，andwhichImuchwishtobeallowedtoquote。Itrelatestotheactionofonemillionthofagrainofatropineontheeye。Nowwillyoubesokind，wheneveryoucanfindalittleleisure，totellmewhetheryouyourselfhaveobservedthisfact，orbelieveitongoodauthority。Ialsowishtoknowwhatproportionbyweighttheatropineboretothewatersolution，andhowmuchofthesolutionwasappliedtotheeye。ThereasonwhyIamsoanxiousonthisheadisthatitgivessomesupporttocertainfactsrepeatedlyobservedbymewithrespecttotheactionofphosphateofammoniaonDrosera。The1/4000000ofagrainabsorbedbyaglandclearlymakesthetentaclewhichbearsthisglandbecomeinflected;andIamfullyconvincedthat1/20000000ofagrainofthecrystallisedsalt（i。e。
containingaboutone—thirdofitsweightofwaterofcrystallisation）doesthesame。NowIamquiteunhappyatthethoughtofhavingtopublishsuchastatement。Itwillbeofgreatvaluetometobeabletogiveanyanalogousfactsinsupport。ThecaseofDroseraisallthemoreinterestingastheabsorptionofthesaltoranyotherstimulantappliedtotheglandcausesittotransmitamotorinfluencetothebaseofthetentaclewhichbearsthegland。
Prayforgivemefortroublingyou，anddonottroubleyourselftoanswerthisuntilyourhealthisfullyre—established。
Praybelieveme，Yoursverysincerely，CHARLESDARWIN。
[Duringthesummerof1874hewasatworkonthegenusUtricularia，andhewrote（July16th）toSirJ。D。Hookergivingsomeaccountoftheprogressofhiswork:——
"IamrathergladyouhavenotbeenabletosendUtricularia，forthecommonspecieshasdrivenF。andmealmostmad。ThestructureisMOST
complex。ThebladderscatchamultitudeofEntomostraca，andlarvaeofinsects。Themechanismforcaptureisexcellent。Butthereismuchthatwecannotunderstand。FromwhatIhaveseento—day，Istronglysuspectthatitisnecrophagous，i。e。thatitcannotdigest，butabsorbsdecayingmatter。"
HewasindebtedtoLadyDorothyNevillforspecimensofthecuriousUtriculariamontana，whichisnotaquaticliketheEuropeanspecies，butgrowsamongthemossanddebrisonthebranchesoftrees。Tothisspeciesthefollowingletterrefers:]
CHARLESDARWINTOLADYDOROTHYNEVILL。
DownSeptember18[1874]。
DearLadyDorothyNevill，Iamsomuchobligedtoyou。IwassoconvincedthatthebladderswerewiththeleavesthatIneverthoughtofremovingthemoss，andthiswasverystupidofme。Thegreatsolidbladder—likeswellingsalmostonthesurfacearewonderfulobjects，butarenotthetruebladders。TheseI
foundontherootsnearthesurface，anddowntoadepthoftwoinchesinthesand。Theyareastransparentasglass，from1/20to1/100ofaninchinsize，andhollow。TheyhavealltheimportantpointsofstructureofthebladdersofthefloatingEnglishspecies，andIfeltconfidentIshouldfindcapturedprey。AndsoIhavetomydelightintwobladders，withclearproofthattheyhadabsorbedfoodfromthedecayingmass。ForUtriculariaisacarrion—feeder，andnotstrictlycarnivorouslikeDrosera。
Thegreatsolidbladder—likebodies，Ibelieve，arereservoirsofwaterlikeacamel’sstomach。AssoonasIhavemadeafewmoreobservations，I
meantobesocruelastogiveyourplantnowater，andobservewhetherthegreatbladdersshrinkandcontainairinsteadofwater;Ishallthenalsowashallearthfromallroots，andseewhethertherearetruebladdersforcapturingsubterraneaninsectsdowntotheverybottomofthepot。Nowshallyouthinkmeverygreedy，ifIsaythatsupposingthespeciesisnotveryprecious，andyouhaveseveral，willyougivemeonemoreplant，andifso，pleasetosenditto"OrpingtonStation，S。E。R。，tobeforwardedbyfootmessenger。"
IhavehardlyeverenjoyedadaymoreinmylifethanIhavethisday’swork;andthisIowetoyourLadyship’sgreatkindness。
Theseedsareverycuriousmonsters;IfancyofsomeplantalliedtoMedicago，butIwillshowthemtoDr。Hooker。
Yourladyship’sverygratefully，CH。DARWIN。
CHARLESDARWINTOJ。D。HOOKER。
Down，September30，1874。
MydearH。，YourmagnificentpresentofAldrovandahasarrivedquitesafe。Ihaveenjoyedgreatlyagoodlookattheshutleaves，oneofwhichIcutopen。
ItisanaquaticDionaea，whichhasacquiredsomestructuresidenticalwiththoseofUtricularia！
IftheleavesopenandIcantransferthemopenunderthemicroscope，I
willtrysomeexperiments，formortalmancannotresistthetemptation。IfIcannottransfer，Iwilldonothing，forotherwiseitwouldrequirehundredsofleaves。
Youareagoodmantogivemesuchpleasure。
Yoursaffectionately，C。DARWIN。
[Themanuscriptof’InsectivorousPlants’wasfinishedinMarch1875。Heseemstohavebeenmorethanusuallyoppressedbythewritingofthisbook，thushewrotetoSirJ。D。HookerinFebruary:——
"Youaskaboutmybook，andallthatIcansayisthatIamreadytocommitsuicide;Ithoughtitwasdecentlywritten，butfindsomuchwantsrewriting，thatitwillnotbereadytogotoprintersfortwomonths，andwillthenmakeaconfoundedlybigbook。Murraywillsaythatitisnousepublishinginthemiddleofsummer，soIdonotknowwhatwillbetheupshot;butIbegintothinkthateveryonewhopublishesabookisafool。"
ThebookwaspublishedonJuly2nd，1875，and2700copiesweresoldoutoftheeditionof3000。]
CHAPTER2。XIV。
THE’POWEROFMOVEMENTINPLANTS。’
1880。
[Thefewsentencesintheautobiographicalchaptergivewithsufficientclearnesstheconnectionbetweenthe’PowerofMovement，’andoneoftheauthor’searlierbooks，thaton’ClimbingPlants。’Thecentralideaofthebookisthatthemovementsofplantsinrelationtolight，gravitation，etc。，aremodificationsofaspontaneoustendencytorevolveorcircumnutate，whichiswidelyinherentinthegrowingpartsofplants。
Thisconceptionhasnotbeengenerallyadopted，andhasnottakenaplaceamongthecanonsoforthodoxphysiology。ThebookhasbeentreatedbyProfessorSachswithafewwordsofprofessorialcontempt;andbyProfessorWiesnerithasbeenhonouredbycarefulandgenerouslyexpressedcriticism。
Mr。ThiseltonDyer（’CharlesDarwin’（’Nature’Series），page41。）haswellsaid:"Whetherthismasterlyconceptionoftheunityofwhathashithertoseemedachaosofunrelatedphenomenawillbesustained，timealonewillshow。ButnoonecandoubttheimportanceofwhatMr。Darwinhasdone，inshowingthatforthefuturethephenomenaofplantmovementcanandindeedmustbestudiedfromasinglepointofview。"
Theworkwasbeguninthesummerof1877，afterthepublicationof’DifferentFormsofFlowers，’andbytheautumnhisenthusiasmforthesubjectwasthoroughlyestablished，andhewrotetoMr。Dyer:"Iamallonfireatthework。"Atthistimehewasstudyingthemovementsofcotyledons，inwhichthesleepofplantsistobeobservedinitssimplestform;inthefollowingspringhewastryingtodiscoverwhatusefulpurposethesesleep—movementscouldserve，andwrotetoSirJosephHooker（March25th，1878）:——
"IthinkwehavePROVEDthatthesleepofplantsistolessentheinjurytotheleavesfromradiation。Thishasinterestedmemuch，andhascostusgreatlabour，asithasbeenaproblemsincethetimeofLinnaeus。Butwehavekilledorbadlyinjuredamultitudeofplants:N。B。——Oxaliscarnosawasmostvaluable，butlastnightwaskilled。"
Hislettersofthisperioddonotgiveanyconnectedaccountoftheprogressofthework。Thetwofollowingaregivenasbeingcharacteristicoftheauthor:]
CHARLESDARWINTOW。THISELTONDYER。
Down，June2，1878。
MydearDyer，IremembersayingthatIshoulddieadisgracedmanifIdidnotobserveaseedlingCactusandCycas，andyouhavesavedmefromthishorriblefate，astheymovesplendidlyandnormally。ButIhavetwoquestionstoask:
theCycasobservedwasahugeseedinabroadandveryshallowpotwithcocoa—nutfibreasIsuppose。ItwasnamedonlyCycas。WasitCycaspectinata？IsupposethatIcannotbewronginbelievingthatwhatfirstappearsabovegroundisatrueleaf，forIcanseenostemoraxis。
Lastly，youmayrememberthatIsaidthatwecouldnotraiseOpuntianigricans;nowImustconfesstoapieceofstupidity;onedidcomeup，butmygardenerandselfstaredatit，andconcludedthatitcouldnotbeaseedlingOpuntia，butnowthatIhaveseenoneofO。basilaris，Iamsureitwas;Iobserveditonlycasually，andsawmovements，whichmakesmewishtoobservecarefullyanother。Ifyouhaveanyfruit，willMr。Lynch（Mr。
R。I。Lynch，nowCuratoroftheBotanicGardenatCambridgewasatthistimeintheRoyalGardens，Kew。）besokindastosendonemore？
Iamworkingawaylikeaslaveatradicles[roots]andatmovementsoftrueleaves，forIhaveprettywelldonewithcotyledons……
ThatwasanEXCELLENTletterabouttheGardens（ThisreferstoanattempttoinducetheGovernmenttoopentheRoyalGardensatKewinthemorning。）:
Ihadhopedthattheagitationwasover。Politiciansareapoortrucklinglot，for[they]mustseethewretchedeffectsofkeepingthegardensopenalldaylong。
Yourevertroublesomefriend，CH。DARWIN。
CHARLESDARWINTOW。THISELTONDYER。
4BryanstonSt。，PortmanSquare，November21[1878]。
MydearDyer，ImustthankyouforallthewonderfultroublewhichyouhavetakenabouttheseedsofImpatiens，andonscoresofotheroccasions。Itintruthmakesmefeelashamedofmyself，andIcannothelpthinking:"OhLord，whenheseesourbookhewillcryout，isthisallforwhichIhavehelpedsomuch！"Inseriousness，Ihopethatwehavemadeoutsomepoints，butI
fearthatwehavedoneverylittleforthelabourwhichwehaveexpendedonourwork。Wearehereforaweekforalittlerest，whichIneeded。
IfIrememberright，November30th，istheanniversaryattheRoyal，andI
fearSirJosephmustbealmostatthelastgasp。IshallbegladwhenheisnolongerPresident。
Yoursverysincerely，CH。DARWIN。
[Inthespringofthefollowingyear，1879。Whenhewasengagedinputtinghisresultstogether，hewrotesomewhatdespondinglytoMr。Dyer:"Iamoverwhelmedwithmynotes，andalmosttoooldtoundertakethejobwhichI
haveinhand——i。e。movementsofallkinds。Yetitisworsetobeidle。"
Lateronintheyear，whentheworkwasapproachingcompletion，hewrotetoProf。Carus（July17，1879），withrespecttoatranslation:——
"TogetherwithmysonFrancis，IampreparingaratherlargevolumeonthegeneralmovementsofPlants，andIthinkthatwehavemadeoutagoodmanynewpointsandviews。
"IfearthatourviewswillmeetagooddealofoppositioninGermany;butwehavebeenworkingveryhardforsomeyearsatthesubject。
"IshallbeMUCHpleasedifyouthinkthebookworthtranslating，andproof—sheetsshallbesentyou，whenevertheyareready。"
Intheautumnhewashardatworkonthemanuscript，andwrotetoDr。Gray（October24，1879）:——
"Ihavewrittenaratherbigbook——moreisthepity——onthemovementsofplants，andIamnowjustbeginningtogoovertheMS。forthesecondtime，whichisahorridbore。"
Onlytheconcludingpartofthenextletterreferstothe’PowerofMovements’:]
CHARLESDARWINTOA。DECANDOLLE。
May28，1880。
MydearSir，Iamparticularlyobligedtoyouforhavingsokindlysendmeyour’Phytographie’（Abookonthemethodsofbotanicalresearch，moreespeciallyofsystematicwork。）;forifIhadmerelyseenitadvertised，I
shouldnothavesupposedthatitcouldhaveconcernedme。Asitis，Ihavereadwithverygreatinterestaboutaquarter，butwillnotdelaylongerthankingyou。Allthatyousayseemstomeveryclearandconvincing，andasinallyourwritingsIfindalargenumberofphilosophicalremarksnewtome，andnodoubtshallfindmanymore。TheyhaverecalledmanyapuzzlethroughwhichIpassedwhenmonographingtheCirripedia;andyourbookinthosedayswouldhavebeenquiteinvaluabletome。IthaspleasedmetofindthatIhavealwaysfollowedyourplanofmakingnotesonseparatepiecesofpaper;Ikeepseveralscoresoflargeportfolios，arrangedonverythinshelvesabouttwoinchesapart，fastenedtothewallsofmystudy，andeachshelfhasitspropernameortitle;andIcanthusputatonceeverymemorandumintoitsproperplace。Yourbookwill，Iamsure，beveryusefultomanyyoungstudents，andIshallbegmysonFrancis（whointendstodevotehimselftothephysiologyofplants）toreaditcarefully。