OncemoreandthistimeinamoreseriousfashionIamthevictimofmyunthinkingenthusiasm。Hardlyistheoperationcompletedwhenthetipsofmyfingersbegintohurtingoodearnest，especiallyinthemoredelicatepartprotectedbytheedgeofthenail。Thefeelingislikethesharppainofasorethatisbeginningtofester。Alltherestofthedayandallthroughthenight，thepainpersists，troublesomeenoughtorobmeofmysleep。Itdoesnotquietdownuntilthefollowingday，aftertwenty-fourhoursofpettytorment。
Howdidthisnewmisadventurebefallme？Ihadnothandledthecaterpillars:
indeed，therewereveryfewoftheminthenestatthetime。Ihadcomeuponnoshedskins，forthemoultsdonottakeplaceinsidethesilkenpurse。Whenthemomenthascometodoffthesecondcostume，thatoftheredmosaic，thecaterpillarsclusteroutside，onthedomeoftheirdwelling，andthereleaveinasingleheaptheiroldclothesentangledwithbitsofsilk。Whatislefttoexplaintheunpleasantconsequencestowhichthehandlingofthenestexposesus？
Thebrokenredbristlesareleft，thefallenhairsformingadustthatisinvisiblewithoutaverycarefulexamination。ForalongtimetheProcessionariescrawlandswarmaboutthenest；theypasstoandfro，penetratingthethicknessofthewallwhentheygotothepasturesandwhentheyreturntotheirdormitory。Whethermotionlessoronthemove，theyareconstantlyopeningandclosingtheirapparatusofinformation，thedorsalmouths。Atthemomentofclosing，thelipsoftheseslits，rollingoneachotherlikethecylindersofaflattening-mill，catchholdofthefluffnearthem，tearitoutandbreakitintofragmentswhichthebottomofthepocket，presentlyreascending，shootsoutside。
Thusmyriadsofirritantparticlesaredisseminatedandsubtlyintroducedintoeverypartofthenest。TheshirtofNessusburnttheveinsofwhosoworeit；thesilkoftheProcessionary，anotherpoisonedfabric，setsonfirethefingersthathandleit。
Theloathsomehairslongretaintheirvirulence。Iwasoncesortingoutsomehandfulsofcocoons，manyofwhichwerediseased。Asthehardnessofthecontentswasusuallyanindicationthatsomethingwaswrong，Itoreopenthedoubtfulcocoonswithmyfingers，inordertosavethenon-contaminatedchrysalids。Mysortingwasrewardedwiththesamekindofpain，especiallyundertheedgesofthenails，asIhadalreadysufferedwhentearingthenests。
ThecauseoftheirritationonthisoccasionwassometimesthedryskindiscardedbytheProcessionaryonbecomingachrysalisandsometimestheshrivelledcaterpillarturnedintoasortofchalkycylinderthroughtheinvasionofthemalignantfungus。Sixmonthslater，thesewretchedcocoonswerestillcapableofproducingrednessandirritation。
Examinedunderthemicroscope，therussethairs，thecauseoftheitching，arestiffrods，verysharpateitherendandarmedwithbarbsalongtheupperhalf。Theirstructurehasabsolutelynothingincommonwithnettle-hairs，thosetaperingphialswhosehardpointsnapsoff，pouringanirritantfluidintothetinywound。
TheplantfromwhoseLatinname，Urtica，wederivethewordurticationborrowedthedesignofitsweaponfromthefangsofthevenomousserpents；
itobtainsitseffect，notbythewound，butbythepoisonintroducedintothewound。TheProcessionaryemploysadifferentmethod。Thehairs，whichhavenaughtresemblingtheampullaryreservoirofthenettle-hairs，mustbepoisonedonthesurface，liketheassegaisoftheKafirsandZulus。
Dotheyreallypenetratetheepidermis？Aretheylikethesavage’sjavelin，whichcannotbeextractedonceithasgonein？Withtheirbarbs，dotheyenterallthemoredeeplybecauseofthequiveringoftheoutragedflesh？Thereisnogroundforbelievinganythingofthekind。InvaindoIscrutinizetheinjuredspotthroughthemagnifying-glass；
Icanseenosignoftheimplanteddart。NeithercouldRé；aumur，whenanencounterwiththeOakProcessionarysethimscratchinghimself。
Hehadhissuspicions，butcouldstatenothingdefinitely。
No；despitetheirsharppointsandtheirbarbs，whichmakethem，underthemicroscope，suchformidablespears，theProcessionary’srussethairsarenotdartsdesignedtoimbedthemselvesintheskinandtoprovokeirritationbypricking。
Manycaterpillars，allmostinoffensive，haveacoatofbristleswhich，underthemicroscope，resolvethemselvesintobarbedjavelins，quiteharmlessinspiteoftheirthreateningaspect。Letmementionacoupleofthesepeaceablehalberdiers。
Earlyinspring，wesee，crossingthepaths，abriskly-movingcaterpillarwhoinspiresrepugnancebyhisferocioushairiness，whichrippleslikeripecorn。Theancientnaturalists，withtheirartlessandpicturesquenomenclature，calledhimtheHedgehog。Thetermisworthyofthecreature，which，inthemomentofdanger，rollsitselfuplikeaHedgehog，presentingitsspinyarmouronallsidestotheenemy。Onitsbackisadensemixtureofblackhairsandhairsofashen-gray；whileonthesidesandfore-partofthebodyisastiffmaneofbrightrusset。Black，greyorrusset，allthisfierce-lookingcoatisheavilybarbed。
Onehesitatestotouchthishorrorwiththefinger-tips。Still，encouragedbymyexample，seven-year-oldPaul，withhistenderchild’sskin，gathershandfulsoftherepulsiveinsectwithnomoreapprehensionthanifhewerepickingabunchofviolets。Hefillshisboxeswithit；herearsitonelm-leavesandhandlesitdaily，forheknowsthatfromthisfrightfulcreaturehewillonedayobtainasuperbMothCheloniacaja，LINN。，cladinscarletvelvet，withthelowerwingsredandtheupperwhite，sprinkledwithbrownspots。
Whatresultedfromthechild’sfamiliaritywiththeshaggycreature？
Notevenatraceofitchingonhisdelicateskin。Idonotspeakofmine，whichistannedbytheyears。
Intheosier-bedsofourlocalstream，therushingAygues，athornyshrubaboundswhich，attheadventofautumn，iscoveredwithaninfinityofverysourredberries。Itscrabbedboughs，whichbearbutlittleverdure，arehiddenundertheirclustersofvermilionballs。
ItisthesallowthornorseabuckthornHippophaë；rhamnoides。
InApril，averyhairybutratherprettycaterpillarlivesattheexpenseofthisshrub’sbuddingleaves。Hehasonhisbackfivedensetuftsofhair，setsidebysideandarrangedlikethebristlesofabrush，tuftsdeep-blackinthecentreandwhiteattheedges。Hewavestwodivergentplumesinfrontofhimandsportsathirdonhiscrupper，likeafeatherytail。Thesethreeareblackhair-pencilsofextremedelicacy。
HisgreyishMoth，flattenedmotionlessonthebark，stretcheshislongfore-legs，oneagainsttheother，infrontofhim。Youwouldtakethem，atafirstglance，forantennaeofexaggeratedproportions。ThisposeoftheextendedlimbshaswontheinsectthescientificlabelofOrgyia，arm’slength；andalsothevulgarandmoreexpressivedenominationofPatteé；tendue，oroutstretchedpaw。
LittlePaulhasnotfailed，withmyaid，toreartheprettybearerofthetuftsandbrushes。Howmanytimes，withhissensitivefinger，hashenotstrokedthecreature’sfurrycostume？Hefounditsofterthanvelvet。Andyet，enlargedunderthemicroscope，thecaterpillar’shairsarehorriblebarbedspears，nolessmenacingthanthoseoftheProcessionary。
Theresemblancegoesnofarther:handledwithoutprecautions，thetuftedcaterpillardoesnotprovokeevenasimplerash。Nothingcouldbemoreharmlessthanhiscoat。
Itisevident，then，thatthecauseoftheirritationlieselsewherethaninthebarbs。Ifthebarbedbristleswereenoughtopoisonthefingers，mosthairycaterpillarswouldbedangerous，fornearlyallhavespinybristles。
Wefind，onthecontrary，thatvirulenceisbestoweduponaverysmallnumber，whicharenotdistinguishedfromtherestbyanyspecialstructureofthehair。
Thatthebarbshaveaparttoplay，thatoffixingtheirritantatomupontheepidermis，ofkeepingitanchoredinitsplace，is，afterall，possible；buttheshootingpainscannotbyanymeansbecausedbythemereprickofsodelicateaharpoon。
Muchlessslender，thehairsclusteredintopadsonthepricklypearsareferociouslybarbed。Woetothefingersthathandlethiskindofvelvettooconfidently！Attheleasttouchtheyarepiercedwithharpoonswhoseextractioninvolvesaseveretaxuponourpatience。
Otherinconveniencethereislittleornone，fortheactionofthebarbisinthiscasepurelymechanical。Supposing——averydoubtfulthing——thattheProcessionary’shairscouldpenetrateourskin，theywouldactlikewise，onlywithlesseffect，iftheyhadmerelytheirsharppointsandtheirbarbs。Whatthendotheypossessinaddition？
Theymusthave，notinsidethem，likethehairsofthenettle，butoutside，onthesurface，anirritantagent；theymustbecoatedwithapoisonousmixture，whichmakesthemactbysimplecontact。
Letusremovethisvirus，bymeansofasolvent；andtheProcessionary’sdarts，reducedtotheirinsignificantmechanicalaction，willbeharmless。
Thesolvent，ontheotherhand，ridofallhairsbyfiltration，willbechargedwiththeirritantelement，whichweshallbeabletotestwithouttheagencyofthehairs。Isolatedandconcentrated，thestingingelement，farfromlosingbythistreatment，oughttogaininvirulence。Soreflectiontellsus。
Thesolventstriedareconfinedtothree:water，spiritsofwineandsulphuricether。Iemploythelatterbypreference，althoughtheothertwo，spiritsofwineespecially，haveyieldedsatisfactoryresults。Tosimplifytheexperiment，insteadofsubmittingtotheactionofthesolventtheentirecaterpillar，whowouldcomplicatetheextractwithhisfatsandhisnutritivejuices，Iprefertoemploythecastskinalone。
Ithereforecollect，ontheonehand，theheapofdryskinswhichthemoultofthesecondphasehasleftonthedomeofthesilkendwellingand，ontheotherhand，theskinswhichthecaterpillarshaverejectedintheircocoonsbeforebecomingchrysalids；andIleavethetwolotstoinfuse，separately，insulphuricetherfortwenty-fourhours。Theinfusioniscolourless。
Theliquid，carefullyfiltered，isexposedtospontaneousevaporation；
andtheskinsarerinsedwithetherinthefilter，severaltimesover。
Therearenowtwoteststobemade:onewiththeskinsandonewiththeproductofmaceration。Thefirstisasconclusiveascanbe。
Hairyasinthenormalstateandperfectlydried，theskinsofbothlots，drainedbytheether，producenottheslightesteffect，althoughIrubmyselfwiththem，withouttheleastcaution，atthejunctureofthefingers，aspotverysensitivetostinging。
Thehairsarethesameasbeforetheactionofthesolvent:theyhavelostnoneoftheirbarbs，oftheirjavelin-points；andyettheyareineffectual。
Theyproducenopainorinconveniencewhatever。Deprivedoftheirtoxicsmearing，thesethousandsofdartsbecomesomuchharmlessvelvet。TheHedgehogCaterpillarandtheBrushCaterpillararenotmoreinoffensive。
Thesecondtestismorepositiveandsoconclusiveinitspainfuleffectsthatonehardlylikestotryitasecondtime。Whentheetherealinfusionisreducedbyspontaneousevaporationtoafewdrops，Isoakinitaslipofblotting-paperfoldedinfour，soastoformasquaremeasuringsomethingoveraninch。Toounsuspectingofmyproduct，Idothingsonalavishscale，bothasregardsthesuperficialareaofmypoorepidermisandthequantityofthevirus。ToanyonewhomightwishtorenewtheinvestigationIshouldrecommendalessgenerousdose。Lastly，thesquareofpaper，thatnovelsortofmustard-plaster，isappliedtotheundersurfaceofthefore-arm。Athinwaterproofsheetingcoversit，topreventitfromdryingtoorapidly；andabandageholdsitinplace。
Forthespaceoftenhours，Ifeelnothing；thenIexperienceanincreasingitchandaburningsensationacuteenoughtokeepmeawakeforthegreaterpartofthenight。Nextday，aftertwenty-fourhoursofcontact，thepoulticeisremoved。Aredmark，slightlyswollenandveryclearlyoutlined，occupiesthesquarewhichthepoisonedpapercovered。
Theskinfeelssore，asthoughithadbeencauterized，andlooksasroughasshagreen。Fromeachofitstinypustulestricklesadropofserousfluid，whichhardensintoasubstancesimilarincolourtogum-arabic。
Thisoozingcontinuesforacoupleofdaysandmore。Thentheinflamationabates；thepain，hithertoverytrying，quietsdown；theskindriesandcomesoffinlittleflakes。Allisover，excepttheredmark，whichremainsforalongtime，sotenaciousinitseffectsisthisextractofProcessionary。
Threeweeksaftertheexperiment，thelittlesquareonthefore-armsubjectedtothepoisonisstilldiscoloured。
Forthusbrandingone’sself，doesoneatleastobtainsomesmallreward？
Yes。Alittletruthisthebalmspreaduponthewound；andindeedtruthisasovereignbalm。Itwillcomepresentlytosolaceusformuchgreatersufferings。
Forthemoment，thispainfulexperimentshowsusthattheirritationhasnotasitsprimarycausethehairinessoftheProcessionary。Hereisnohair，nobarb，nodart。Allofthathasbeenretainedbythefilter。
Wehavenothingnowbutapoisonousagentextractedbythesolvent，theether。Thisirritantelementrecalls，toacertainextent，thatofcantharides，whichactsbysimplecontact。Mysquareofpoisonedblotting-paperwasasortofplaster，which，insteadofraisingtheepidermisingreatblisters，makesitbristlewithtinypustules。
Thepartplayedbythebarbedhairs，thoseatomswhichtheleastmovementoftheairdisseminatesinalldirections，isconfinedtoconveyingtoourfaceandhandstheirritantsubstanceinwhichtheyareimpregnated。
Theirbarbsholdtheminplaceandthuspermitthevirustoact。Itisevenprobablethat，bymeansofslightscratcheswhichwouldotherwisepassunnoticed，theyassisttheactionofthestingingfluid。
ShortlyafterhandlingtheProcessionaries，adelicateepidermisbecomestumefied，redandpainful。Withoutbeingimmediate，theactionofthecaterpillarisprompt。Theextractmadewithether，ontheotherhand，causespainandrubefactiononlyafteralongishinterval。Whatdoesitneedtoproducemorerapidulceration？Toallappearances，theactionofthehairs。
Thedirectstingingcausedbythecaterpillarisnothinglikesoseriousasthatproducedbytheetherealextractconcentratedinafewdrops。Neverbefore，inmymostpainfulmisadventures，whetherwiththesilkenpursesortheirinhabitants，haveIseenmyskincoveredwithserouspustulesandpeelingoffinflakes。Thistimeitisaveritablesore，anythingbutpleasingtotheeye。
Theaggravationiseasilyexplained。Isoakedintheethersomefiftydiscardedskins。Thefewdropswhichremainedaftertheevaporationandwhichwereabsorbedbythesquareofblotting-paperrepresented，therefore，thevirulenceofasingleinsectfiftytimesincreased。Mylittleblistering-plasterwasequivalenttothecontactoffiftycaterpillarsatthesamespot。Thereisnodoubtthat，ifweleftthemtosteepinconsiderablenumbers，weshouldobtainextractsofreallyformidablestrength。Itisquitepossiblethatmedicalsciencewillonedaymakegooduseofthispowerfulcounter-irritant，whichisutterlydifferentfromcantharides。
Whethervoluntaryvictimsofourcuriosity，which，whileaffordingnoothersatisfactionthanthatofknowledge，exposesustoanintolerableitch，orsufferersthroughanaccident，whatcanwedotogivealittlerelieftotheirritationcausedbytheProcessionary？Itisgoodtoknowtheoriginoftheevil，butitwouldbebettertoapplyaremedy。
Oneday，withbothhandssorefromtheprolongedexaminationofanest，Itrywithoutsuccesslotionsofalcohol，glycerine，oilandsoapsuds。
Nothingdoesanygood。IthenrememberapalliativeemployedbyRé；aumuragainstthestingoftheOakProcessionary。Withouttellingushowhecametoknowofthestrangespecific，themasterrubbedhimselfwithparsleyandfeltagooddealthebetterforit。Headdsthatanyotherleafwouldprobablyassuagetheirritationinthesameway。
Thisisafittingoccasionforreopeningthesubject。Here，inacornerofthegarden，isparsley，greenandabundantasonecouldwish。Whatotherplantcanwecomparewithit？Ichoosethepurslain，thespontaneousguestofmyvegetable-beds。Mucilaginousandfleshyasitis，itreadilycrushes，yieldinganemollientliniment。Irubonehandwithparsleyandtheotherwithpurslain，pressinghardenoughtoreducetheleavestoapaste。Theresultdeservesattention。
Withtheparsley，theburningisalittlelessacute，itistrue，but，thoughrelieved，itpersistsforalongtimeyetandcontinuestroublesome。
Withthepurslain，thepettytortureceasesalmostatonceandsocompletelythatInolongernoticeit。Mynostrumpossessesincontestablevirtues。
Irecommenditquietly，withoutblatantadvertisement，toanyonewhomaybepersecutedbytheProcessionary。Foresters，intheirwaruponcaterpillars’
nests，shouldfindgreatrelieffromit。
Ihavealsoobtainedgoodresultswiththeleavesofthetomatoandthelettuce；and，withoutpursuingthisbotanicalsurveyfurther，Iremainconvinced，withReaumur，thatanytenderjuicyfoliagewouldpossessacertainefficacy。
Asforthemodeofactionofthisspecific，IadmitthatIdonotunderstandit，anymorethanIcanperceivethemodeofactionofthecaterpillar’svirus。Moliè；re’smedicalstudentexplainedthesoporificpropertiesofopiumbysaying:
\"Quiaestineovirtusdormitavacujusestproprietassensusassoupire。\"
Letussaylikewise:thecrushedherbcalmstheburningitchbecauseitpossessesacalmingvirtuewhosepropertyistoassuageitching。
Thequipisagooddealmorephilosophicalthanitlooks。Whatdoweknowofourremediesorofanything？Weperceiveeffects，butwecannotgetbacktotheircauses。
Inmyvillageandforsomedistancearoundit，thereisapopularbeliefthattorelievethepainofaWasp’sorBee’sstingallthatweneeddoistorubthepartstungwiththreesortsofherbs。Take，theysay，threekindsofherbs，thefirstthatcometohand，makethemintoabunchandrubhard。Theprescription，byallaccounts，isinfallible。
Ithoughtatfirstthatthiswasoneofthosetherapeuticabsurditieswhichhavetheirbirthinrusticimaginations。Aftermakingatrial，I
admitthatwhatsoundslikeanonsensicalremedysometimeshassomethinggenuineaboutit。FrictionwiththreekindsofherbsdoesactuallydeadenthestingoftheWasporBee。
Ihastentoaddthatthesamesuccessisachievedwithasingleherb；
andsotheresultagreeswithwhattheparsleyandpurslainhavetaughtusinrespectoftheirritationcausedbytheProcessionary。
Whythreeherbswhenoneisenough？Threeisthepreeminentlyluckynumber；itsmacksofwitchcraft，whichisfarfromdetractingfromthevirtuesoftheunguent。Allrusticmedicinehasatouchofmagicaboutit；andthereismeritindoingthingsbythrees。
Perhapsthespecificofthethreeherbsmayevendatebacktothemateriamedicaofantiquity。Dioscoridesrecommendstriphyllon:itis，hestates，goodforthebiteofvenomousserpents。Todeterminethiscelebratedthree-leavedplantexactlywouldnotbeeasy。Isitacommonclover？Thepsoralea，withitspitchyodour？Themenyanthes，oruck-bean，thatinmateofthechillypeat-bogs？Theoxalis，thewood-sorrelofthecountry-side？Wecannottellforcertain。Thebotanyofthosedayswasinnocentofthedescriptiveconscientiousnessofours。Theplantwhichactedasapoison-antidotegroupeditsleavesbythrees。Thatisitsessentialcharacteristic。
Againthecabalisticnumber，essentialtomedicalvirtuesasconceivedbythefirsthealers。Thepeasant，atenaciousconservative，haspreservedtheancientremedy，but，byahappyinspiration，haschangedthethreeoriginalleavesintothreedifferentherbs；hehaselaboratedthetriphyllonintothethreefoldfoliagewhichhecrushesontheBee’ssting。IseemtoperceiveacertainrelationbetweentheseartlesswaysandthecrushingofparsleyasdescribedbyRé；aumur。7，TheLifeoftheCaterpillar，byJ。HenriFabre，1916TheLifeoftheCaterpillar，byJ。HenriFabre，1916VII:THEARBUTUSCATERPILLAR
IHAVEnotfoundmanyspeciesofurticatingcaterpillarsinthesmallcornerofmyinvestigations。Iknowoftwoonly:thePineCaterpillarandtheArbutusCaterpillar。ThelatterbelongstothegenusLiparis。HisMoth，whoisaglorioussnowywhite，withthelastringsoftheabdomenbrightrusset，isverylikeLiparisauriflua，FAB。，fromwhomshediffersnotonlyinsize-sheissmaller——but，aboveall，inthefieldofoperationsselectedbyhercaterpillar。Isthespeciesclassifiedinourlists？Idonotknow；andreallyitishardlyworthwhiletoenquire。WhatdoesaLatinnamematter，whenonecannotmistaketheinsect？IshallbesparingofdetailconcerningtheArbutusCaterpillar，forheisfarlessinterestinginhishabitsthanthePineProcessionary。
Onlyhisravagesandhispoisondeserveseriousattention。
OntheSé；rignanhills，sunnyheightsuponwhichtheMediterraneanvegetationcomestoanend，thearbutus，orstrawberry-tree，abounds:
amagnificentshrub，withlustrousevergreenfoliage，vermilionfruit，roundandfleshyasstrawberries，andhangingclustersoflittlewhitebellsresemblingthoseofthelilyofthevalley。WhenthefrostscomeattheapproachofDecember，nothingcouldbemorecharmingthanthearbutus，deckingitsgayverdurewithbothfruitsandflowers，withcoralballsandplumplittlebells。Aloneofourflora，itcombinesthefloweringofto-daywiththeripeningofyesterday。
Thenthebright-redraspberries——thedarbouses，aswecallthemhere——belovedbytheBlackbird，growsoftandsweettothepalate。Thehousewivespluckthemandmakethemintopreservesthatarenotwithoutmerit。Asfortheshrubitself，whentheseasonforcuttinghascome，itisnot，despiteitsbeauty，respectedbythewoodman。Itserves，likeanytrivialbrushwood，inthemakingoffaggotsforheatingovens。Frequently，too，theshowyarbutusisravagedbyacaterpillaryetmoretobedreadedthanthewoodcutter。Afterthisgluttonhasbeenatit，itcouldnotlookmoredesolatehaditbeenscorchedandblackenedbyfire。
TheMoth，aprettylittle，snow-whiteBombyx，withsuperbantennaryplumesandacotton-wooltippetonherthorax，layshereggsonaleafofthearbutusand，insodoing，startstheevil。
Youseealittlecushionwithpointedends，ratherlessthananinchinlength；awhiteeiderdown，tingedwithrusset，thick，verysoftandformedofhairsfixedwithalittlegumbytheendthatpointstowardstheupperextremityoftheleaf。Theeggsaresunkinthethicknessofthissoftshelter。Theypossessametallicsheenandlooklikesomanynickelgranules。
HatchingtakesplaceinSeptember。Thefirstmealsaremadeattheexpenseofthenativeleaf；thelateronesattheexpenseoftheleavesallaround。
Onesurfaceonlyisnibbled，usuallytheupper；theotherremainsintact，trellisedbythenetworkofveins，whicharetoohornyforthenew-borngrubs。
Theconsumptionofleavesiseffectedwithscrupulouseconomy。Insteadofgrazingathazardandusingupthepasturageatthedictatesofindividualcaprice，theflockprogressesgraduallyfromthebasetothetipoftheleaf，withallheadsrangedinafrontalattack，almostinastraightline。
Notabiteistakenbeyondthisline，untilallthatliesonthissideofitiseatenup。
Asitadvances，theflockthrowsafewthreadsacrossthedenudedportion，wherenothingremainsbuttheveinsandtheepidermisoftheoppositesurface。
Thusiswovenagossamerveilservingasashelterfromthefierceraysofthesunandastheparachutewhichisessentialtotheseweaklings，whomapuffofwindwouldcarryaway。
Astheresultofamorerapiddesiccationontheravagedsurface，theleafsoonbeginstocurlofitsownaccord，curvingintoagondolawhichiscoveredbyacontinuousawningstretchedfromendtoend。Theherbageisthenexhausted。Theflockabandonsitandbeginsagainelsewhereinthenearneighbourhood。
Aftervarioustemporarypasturesofthiskind，inNovember，whenthecoldweatherisathand，thecaterpillarssettlepermanentlyattheendofabough。Nibbledonebyoneontheiruppersurfaces，theleavesoftheterminalbunchdrawclosetotheirneighbours，which，excoriatedintheirturn，dothesame，untilthewholeformsabundle，whichlooksasifithadbeenscorched，lashedtogetherwithmagnificentwhitesilk。Thisisthewinterhabitation，whencethefamily，stillveryfeeble，willnotissueuntilthefineweatherreturns。
Theassemblingofthisleafyframeworkisnotduetoanyspecialindustryonthecaterpillars’part；theydonotstretchtheirthreadsfromleaftoleafandthen，bypullingattheseropes，bringthevariouspiecesofthestructureintocontact。Itismerelytheresultofdesiccationonthenibbledsurfaces。Fixedcables，itistrue，solidlybindtogethertheleavesbroughtclosetooneanotherbythecontractionduetotheiraridity；buttheydonotinanywayplaythepartofamotivemechanismintheworkoftheassemblage。
Nohauling-ropesarehere，nocapstanstomovethetimbers。Thefeeblecreatureswouldbeincapableofsucheffort。Thethinghappensofitself。
Sometimesafloatingthread，theplaythingoftheair，enlacessomeadjacentleaf。Thischancefootbridgetemptstheexplorers，whohastentostriptheaccidentalprize；and，withoutotherlabour，yetonemoreleafbendsofitsownaccordandisaddedtotheenclosure。Forthemostpart，thehouseisbuiltbyeating；alodgingisprocuredbydintofbanqueting。
Acomfortablehouse，tightlyclosedandwell-caulked，proofagainstrainandsnow。We，toguardourselvesagainstdraughts，putsand-bagsagainstthecracksofourdoorsandwindows；theextravagantlittleArbutusCaterpillarappliespipingsofsilk-velvettohisshutters。Thingsshouldbecosyinside，howeverdampthefog。Inbadweather，theraindripsintomyhouse。Theleaf-dwellingknowsnothingofsuchtroubles，sotrueisitthatanimalsoftenenjoyadvantageswhichrelegatehumanindustrytothesecondrank。
Inthisshelterofsilkandfoliage，theworstthreeorfourmonthsoftheyeararepassedinastateofcompleteabstinence。Nooutings；notabiteoffood。InMarch，thistorporceases；andtherecluses，thosestarvingbellies，shifttheirquarters。
Thecommunitynowsplitsupintosquads，whichspreadthemselvesanyhowovertheadjacentverdure。Thisistheperiodofseriousdevastation。Thecaterpillarsnolongerconfinethemselvestonibblingonesurfaceoftheleaf；theirkeenappetitesdemandthewholeofit，downtothestalk。Andnow，stagebystage，haltbyhalt，thearbutusisshornbare。
Thevagabondsdonotreturntotheirwinterdwelling，whichhasbecometoocloselycramped。Theyreassembleingroupsandweave，here，thereandeverywhere，shapelesstents，temporaryhuts，abandonedforothersasthepasturageroundaboutbecomesexhausted。Thedenudedboughs，toallseemingravagedbyfire，takeonthelookofsqualiddrying-groundshungwithrags。
InJune，havingacquiredtheirfullgrowth，thecaterpillarsleavethearbutus-tree，descendtoearthandspinthemselves，amidthedeadleaves，aniggardlycocoon，inwhichtheinsect’shairstosomeextentsupplementitssilk。Amonthlater，theBombyxappears。
Inhisfinaldimensions，thecaterpillarmeasuresnearlyaninchandaquarterinlength。Hiscostumedoesnotlackrichnessororiginality:
ablackskinwithadoublerowoforangespecksontheback；longgreyhairsarrangedinbunches；short，snow-whitetuftsonthesides；andacoupleofbrown-velvetprotuberancesonthefirsttworingsoftheabdomenandalsoonthelastringbutone。
Themostremarkablefeature，however，consistsoftwotinycraters，alwaysopenwide；twocunninglyfashionedgobletswhichmighthavebeenwroughtfromadropofredsealing-wax。Thesixthandseventhsegmentsoftheabdomenaretheonlyonesthatbearthesevermiliongoblets，placedinthemiddleoftheback。Idonotknowthefunctionoftheselittlecups。Perhapstheyshouldberegardedasorgansofinformation，similartothePineProcessionary’sdorsalmouths。
TheArbutusCaterpillarismuchdreadedinthevillage。Woodcutters，faggot-binders，brushwood-gatherers，allareunanimousinrevilinghim。
Theyhavesuchapainfullyvividmemoryoftheirritationthat，whenI
listentothem，Icanhardlyrepressamovementoftheshoulderstorelievetheimaginaryitchinginthemiddleofmyback。Iseemtofeelthearbutus-faggot，ladenwithitsglowingrags，rubbingmybareskin。
Itis，itappears，adisagreeablejobtocutdowntheshrubalivewithcaterpillarsduringthehottestpartofthedayandtoshake，undertheblowsoftheaxe，thatsortofupas-tree，sheddingpoisoninitsshade。
Asforme，Ihavenocomplainttomakeofmyrelationswiththeravagerofthearbutus。Ihaveveryoftenhandledhim；Ihaveappliedhisfurtothetipsofmyfingers，myneckandevenmyface，forhoursatatime；
Ihaverippeduptheneststoextracttheirpopulationsforthepurposeofmyresearches；butIhaveneverbeeninconvenienced。
Saveinexceptionalcircumstances，theapproachofthemoultperhaps，thiswouldneedaskinlesstoughthanmine。
Thethinskinofachilddoesnotenjoythesameimmunity，aswitnesslittlePaul，who，havinghelpedmetoemptysomenestsandtocollecttheinhabitantswithmyforceps，wasforhoursscratchinghisneck，whichwasdottedwithredwheals。Myingenuousassistantwasproudofhissufferingsinthecauseofscience，whichresultedfromheedlessnessandalsoperhapsfrombravado。Intwenty-fourhours，thetroubledisappeared，withoutleavinganyseriousconsequences。
Allthishardlytallieswiththepainfulexperiencesofwhichthewoodcutterstalk。Dotheyexaggerate？Thatishardlycredible；theyaresounanimous。
Thensomethingmusthavebeenlackinginmyexperiments:thepropitiousmomentapparently，theproperdegreeofmaturityinthecaterpillar，thehightemperaturewhichaggravatesthepoison。
Toshowitselfinitsfullseverity，theurticationdemandsthecooperationofcertainundefinedcircumstances；andthiscooperationwaswanting。ChanceperhapswillonedayteachmemorethanIwanttoknow；
Ishallbeattackedinthemannerfamiliartothewoodcuttersandshallpassanightintorment，tossingandturningasthoughonabedoflivecoals。
WhatthedirectcontactofthecaterpillardidnotteachmetheartificesofchemistrywilldemonstratewithaviolencewhichIwasfarfromexpecting。
Itreatthecaterpillarwithether，justasItreatedthesloughofthePineProcessionary。Thenumberofthecreaturestakenfortheinfusion——theyareprettysmallasyet，arescarcelyhalfthesizewhichtheywillattainwhenmature——isaboutahundred。Afteracoupleofdays’maceration，I
filtertheliquidandleaveittoevaporatefreely。WiththefewdropsthatremainIsoakasquareofblotting-paperfoldedinfourandapplyittotheinnersurfaceofmyforearm，withathinrubbersheetandabandage。
ItisanexactrepetitionofwhatIdidwiththePineProcessionary。
Appliedinthemorning，theblisterhardlytakeseffectuntilthefollowingnight。Thenbydegreestheirritationbecomesunendurable；andtheburningsensationissoacutethatIamtormentedeverymomentwiththedesiretotearoffthebandage。HoweverIholdout，butatthecostofasleeplessnight。
HowwellInowunderstandwhatthewoodcutterstellme！Ihadlessthanasquareinchofskinsubjectedtothetorture。WhatwoulditbeifIhadmyback，shoulders，neck，faceandarmstormentedinthisfashion？Ipityyouwithallmyheart，youlabourerswhoaretroubledbythehatefulcreature。
Onthemorrow，theinfernalpaperisremoved。Theskinisredandswollen，coveredwithtinypimplesWhenceoozedropsofserousfluid。Forfivedaystheitchingpersists，withasharp，burningpain，andtherunningfromthepimplescontinues。Thenthedeadskindriesandcomesoffinscabs。
Allisover，savetheredness，whichisstillperceptibleamonthlater。
Thedemonstrationisaccomplished；theArbutusCaterpillar，capableasheisofproducing，undercertainconditions，thesameeffectswhichIobtainbyartificialmeans，fullydeserveshisodiousreputation。8，TheLifeoftheCaterpillar，byJ。HenriFabre，1916TheLifeoftheCaterpillar，byJ。HenriFabre，1916VIII:ANINSECTVIRUS
ONEstepforwardhasbeentaken，butonlyaverylittleoneasyet，intheproblemofthestingingcaterpillars。Thedrenchingwithetherteachesusthathairinessplaysaverysecondarypartinthematter。Withitsdustofbrokenbristles，whichtheleastbreathwaftsinalldirections，itbothersusbydepositingandfixingitsirritantcoatinguponus；butthisvirusdoesnotoriginateinthecreature’sfleece；itcomesfromelsewhere。
Whatisthesourceofit？
Iwillenterintoafewdetails。Perhaps，insodoing，Ishallbeofservicetothenovice。Thesubject，whichisverysimpleandsharplydefined，willshowushowonequestiongivesrisetoanother；howexperimentaltestsconfirmorupsethypotheses，whichare，asitwere，atemporaryscaffolding；
and，lastly，howlogic，thatsevereexaminer，leadsusbydegreestogeneralitieswhicharefarmoreimportantthananythingthatwewereledtoanticipateattheoutset。
And，firstofall，doesthePineProcessionarypossessaspecialglandularstructurewhichelaboratesthevirus，asdo，forinstance，thepoison-glandsoftheWaspsandBees？Bynomeans。Anatomyshowsthattheinternalstructureofthestingingcaterpillarissimilartothatoftheharmlessone。Thereisnothingmoreandnothingless。
Thepoisonousproduct，ofunlocalizedorigin，results，therefore，fromageneralprocessinwhichtheentireorganismisbroughtintoplay。Itshould，inconsequencebefoundintheblood，afterthemannerofureainhigheranimals。Thisisasuggestionofgraveimport，butafterallquitevaluelesswithouttheconclusiveverdictofactualexperiment。
FiveorsixProcessionaries，prickedwiththepointofaneedle，furnishmewithafewdropsofblood。Iallowthesetosoakintoasmallsquareofblotting-paper，whichIthenapplytomyfore-armwithawaterproofbandage。ItisnotwithoutacertainanxietythatIawaittheoutcomeoftheexperiment。Theresultwillshowwhethertheconclusionsalreadyforminginmymindwillreceiveasolidbasisorvanishintothinair。
Atalatehourofthenight，thepainwakesme，apainwhichthistimeisanintellectualjoy。Myanticipationswerecorrect。
Theblooddoesindeedcontainthevenomoussubstance。Itcausesitching，swelling，aburningsensation，anexudationofserumand，lastly，asheddingoftheskin。IlearnmorethanIhadhopedtolearn。Thetestismorevaluablethanthatofmerecontactwiththecaterpillarcouldhavebeen。Insteadoftreatingmyselfwiththesmallquantityofpoisonwithwhichthehairsaresmeared，IhavegonetothesourceoftheirritantsubstanceandI
therebygainanincreaseofdiscomfort。
Veryhappyinmysuffering，whichsetsmeonasafepath，Icontinuemyenquirybyarguingthus。thevirusinthebloodcannotbealivingsubstance，onethattakespartintheworkingoftheorganism；itisrather，likeurea，aformofdecay，anoffthrowofthevitalprocess，awasteproductwhichisexpelledasandwhenitforms。Ifthisbethecase，Ioughttofinditinthecaterpillar’sdroppings，whicharemadeupofboththedigestiveandtheurinaryresidues。
Letusdescribethenewexperiment，whichisnolesspositivethanthelast。Ileaveafewpinchesofverydrydroppings，suchasarefoundinabundanceintheoldnests，tosoakfortwodaysinsulphuricether。
Theliquid，colouredasitiswiththechlorophyllofthecaterpillar’sfood，turnsadirtygreen。ThenIrepeatpreciselytheprocesswhichI
mentionedwhenIwantedtoprovetheinnocuousnessofthehairsdeprivedoftheirpoisonousvarnish。Irefertoitasecondtimeinorderthoroughlytoexplainthemethodpursuedandtosaverepetitioninthevariousexperimentsundertaken。
Theinfusionisfiltered，spontaneouslyevaporatedandreducedtoafewdrops，withwhichIsoakmystinger。Thisconsistsofasmallpieceofblotting-paper，foldedinfourtoincreasethethicknessofthepadandtogiveitagreaterpowerofabsorption。Anareaofasquareinchorlesssuffices；insomecasesitiseventoomuch。Anoviceinthiskindofresearch-work，Iwastoolavishwiththeliniment；andinreturnformygenerosityIhadsuchabadtimethatImakeapointofwarninganyreaderdesirousofrepeatingtheexperimentuponhisownperson。
Fullysoaked，thesquareofpaperisappliedtothefore-arm，ontheinnersurface，wheretheskinismoretender。Asheetofrubbercoversitand，beingwaterproof，guardsagainstthelossofthepoison。Finally，alinenbandagekeepsthewholeinplace。
Ontheafternoonofthe4thofJune1897，amemorabledateforme，I
test，asIhavejustsaid，theethericextractoftheProcessionary’sdroppings。
Allnightlong，Ifeelaviolentitching，aburningsensationandshootingpains。Onthefollowingday，aftertwentyhoursofcontact，Iremovethedressing。
Thevenomousliquid，toolavishlyemployedinmyfearoffailure，hasconsiderablyoverflowedthelimitsofthesquareofpaper。Thepartswhichithastouchedandstillmoretheportioncoveredbythepadareswollenandveryred；moreover，inthelattercase，theskinisridged，wrinkledandmortified。Itsmartsalittleanditches；andthatisall。
Onthefollowingday，theswellingbecomesmorepronouncedandgoesdeepintothemuscles，which，whentouchedwiththefinger，throblikeaninflamedcheek。Thecolourisabrightcarmineandextendsallroundthespotwhichthepapercovered。Thisisduetotheescapeofsomeoftheliquid。Thereisaplentifuldischargeofserum，oozingfromthesoreintinydrops。Thesmartinganditchingincreaseandbecomesointense，especiallyduringthenight，that，togetalittlesleep，Iamdriventoemployapalliative，vaselinewithboraxandalintdressing。
Infivedays’time，ithasdevelopedintoahideousulcer，whichlooksmorepainfulthanitreallyis。Thered，swollenflesh，quiveringanddenudedofitsepidermis，provokescommiseration。Thepersonwhonightandmorningrenewsmydressingoflintandvaselineisalmostsickatthesight。
\"Onewouldthink，\"shesays，\"thatthedogshadbeengnawingyourarm。
Idohopeyouwon’ttryanymoreofthosehorribledecoctions。\"
Iallowmysympatheticnursetotalkawayandamalreadymeditatingfurtherexperiments，someofwhichwillbeequallypainful。Osacredtruth，whatcanrivalthypoweroverusmortals！Thouturnestmypettytormentintocontentment；thoumakestmerejoiceinmyflayedarm！WhatshallI
gainbyitall？Ishallknowwhyawretchedcaterpillarsetsusscratchingourselves。Nothingmore；andthatisenoughforme。
Threeweekslater，newskinisforming，butiscoveredalloverwithpainfullittlepimples。
Theswellingdiminishes；therednesspersistsandisstillverymarked。
Theeffectoftheinfernalpaperlastsalongtime。Attheendofamonth，Istillfeelanitching，aburningirritation，whichisintensifiedbythewarmthofthebed-clothes。Atlast，afortnightlater，allhasdisappearedbuttheredness，ofwhichIshallretainthemarksforalongtimeyet，thoughitgrowsgraduallyfainterandfainter。Itwilltakethreemonthsormoretovanishaltogether。
Wenowhavesomelightontheproblem:theProcessionary’svirusiscertainlyanoff-throwoftheorganicfactory，awasteproductofthelivingedifice。Thecaterpillardiscardsitwithhisexcrement。Butthematerialofthedroppingshasatwofoldorigin:thegreaterpartrepresentsthedigestiveresiduum；therest，inamuchsmallerproportion，iscomposedoftheurinaryproducts。Towhichofthetwodoesthevirusbelong？Beforegoingfarther，letuspermitourselvesadigressionwhichwillassistusinoursubsequentenquiries。LetusaskwhatadvantagestheProcessionaryderivesfromhisurticatingproduct。
Ialreadyheartheanswer:
\"Itisameansofprotection，ofdefence。Withhispoisonedmane，herepelstheenemy。\"
Idonotclearlyperceivethebearingofthisexplanation。Ithinkofthecreature’srecognizedenemies:ofthelarvaofCalosomasycophanta，，whichlivesinthenestsoftheProcessionaryoftheOakandgobblesuptheinhabitantswithneverathoughtoftheirburningfleece；oftheCuckoo，anothermightyconsumer，sowearetold，ofthesamecaterpillars，whogorgesonthemtothepointofimplantinginhisgizzardabristlingcoatoftheirhairs。
IamnotawareiftheProcessionaryofthePinepaysaliketribute。
Idoknowofatleastoneofhisexploiters。ThisisaDermestes，[note1]establisheshimselfinthesilkencityandfeedsupontheremainsofthedefunctcaterpillars。Thisghoulassuresusoftheexistenceofotherconsumers，allfurnishedwithstomachsexpresslyfashionedforsuchhighly-seasonedfare。Foreveryharvestoflivingcreaturesthereisalwaysaharvester。
No，thetheoryofaspecialvirus，expresslypreparedtodefendtheProcessionaryandhisemulatorsinurtication，isnotthelastwordonthesubject。Ishouldfinditdifficulttobelieveinsuchaprerogative。Whyhavethesecaterpillars，morethanothers，needofprotection？Whatreasonswouldmakeofthemacasteapart，endowedwithanexceptionaldefensivevenom？Thepartwhichtheyplayintheentomologicalworlddoesnotdifferfromthatofothercaterpillars，hairyorsmooth。
Itisthenakedcaterpillarswho，indefaultofamanecapableofstrikingaweintotheassailant，ought，onewouldthink，toarmthemselvesagainstdangerandimpregnatethemselveswithcorrosives，insteadofremainingameekandeasyprey。Isitlikelythattheshaggy，bristlingcaterpillarshouldanointhisfleecewithaformidablecosmeticandhissmooth-coatedkinsmanbeunfamiliarwiththechemicalpropertiesofthepoisonbeneathhissatinskin！Thesecontradictionsdonotinspireconfidence。
Havewenothere，rather，apropertycommontoallcaterpillars，smooth-skinnedorhairy？Amongthelatter，theremightbesome，justafew，who，undercertainspecialconditionswhichwillneedtobedefined，wouldbequicktorevealbyurticationthevenomousnatureoftheirorganicrefuse；theothers，thevastmajority，livingoutsidetheseconditions，eventhoughendowedwiththenecessaryproduct，wouldbeinexpertatthestingingbusinessandwouldnotproduceirritationbycontact。Inall，thesamevirusistobefound，resultingfromanidenticalvitalprocess。
Sometimesitisbroughtintoprominencebytheitchingwhichitproduces；
sometimes，indeedmostoften，itremainslatent，unrecognized，ifourartificesdonotintervene。
Whatshalltheseartificesbe？Somethingverysimple。IaddressmyselftotheSilkworm。Iftherebeaninoffensivecaterpillarintheworld，itiscertainlyhe。WomenandchildrentakehimupbythehandfulinourSilkworm-nurseries；
andtheirdelicatefingersarenonetheworseforit。Thesatin-skinnedcaterpillarisperfectlyinnocuoustoaskinalmostastenderashisown。
Butthislackofcausticvenomisonlyapparent。ItreatwithethertheexcretionsoftheSilkworm；andtheinfusion，concentratedintoafewdrops，istestedaccordingtotheusualmethod。Theresultiswonderfullydefinite。Asmartingsoreonthearm，similarinitsmodeofappearanceandinitseffectstothatproducedbythedroppingsoftheProcessionary，assuresmethatlogicwasright。
Yes，theviruswhichmakesonescratchsomuch，whichblistersandeatsawaytheskin，isnotadefensiveproductvestedinonlyafewcaterpillars。
Irecognizeit，withitsinvariableproperties，eveninacaterpillarwhichatfirstsightappearsasthoughitcouldnotpossessanythingofthekind。
TheSilkworm’svirus，besides，isnotunknowninmyvillage。Thecasualobservationofthepeasant-womanhasoutstrippedthepreciseobservationofthemanofscience。ThewomenandgirlsentrustedwiththerearingoftheSilkworm——themagnanarellesastheyarecalled——complainofcertaintribulationscaused，theysay，bylouvenndimagnan，theSilkworms’poison。Thistroubleconsistsofaviolentitchingoftheeyelids，whichbecomeredandswollen。Inthecaseofthemoresusceptible，thereisarashandtheskinpeelsoffthefore-arm，whichtheturned-upsleevesfailtoprotectduringwork。
Inowknowthecauseofthislittletrouble，mypluckymagnanarelles。Itisnotcontactwiththewormthatafflictsyou；youneedhavenofearofhandlinghim。Itisonlythelitterthatyouneeddistrust。There，jumbledupwiththeremainsofthemulberry-leaves，isacopiousmassofdroppings，impregnatedwiththesubstancewhichhasjustsopainfullyeatenintomyskin；thereandthereonlyislouverin，asyoucallit。
Itisareliefmerelytoknowthecauseofone’strouble；butIwillprovideyouwithanotherconsolation。Whenyouremovethelitterandrenewtheleaves，youshouldraisetheirritantdustaslittleaspossible；youshouldavoidliftingyourhandstoyourface，abovealltoyoureyes；anditisjustaswelltoturndownyoursleevesinordertoprotectyourarms。
Ifyoutaketheseprecautions，youwillsuffernounpleasantness。
ThesuccessfulresultobtainedwiththeSilkwormcausedmetoforeseeasimilarsuccesswithanycaterpillarthatImightcomeacross。Thefactsfullyconfirmedmyexpectations。Itestedthestercoralpelletsofvariouscaterpillars，notselected，butjustasthehazardofcollectingprovidedthem:theGreatTortoiseshell，theHeathFritillary，theLargeCabbageButterfly，theSpurgeHawk-moth，theGreatPeacockMoth，theDeath’s-headMoth，thePuss-moth，theTiger-mothandtheArbutusLiparis。Allmytests，withnotasingleexception，broughtaboutstinging，ofvariousdegreesofviolence，itistrue。Iattributethesedifferencesintheresulttothegreaterorlesserquantitiesofthevirusemployed，foritisimpossibletomeasurethedose。
Sotheurticatingexcretioniscommontoallthecaterpillars。Byaveryunexpectedreversionoftheusualorderofthings，thepopularrepugnanceiswell-founded；prejudicebecomestruth:allcaterpillarsarevenomous。
Wemustdrawadistinction，however:withthesamevenomousproperties，someareinoffensiveandothers，farlessnumerous，aretobefeared。Whencecomesthisdifference？
Inotethatthecaterpillarsmarkedoutasstingingliveincommunitiesandweavethemselvesdwellingsofsilk，inwhichtheystayforlongperiods。
Moreover，theyarefurry。OfthisnumberarethePineProcessionary，theOakProcessionaryandthecaterpillarsofvariousLipares。
Letusconsiderthefirst-namedinparticular。Hisnest，avoluminousbagspunatthetipofabranch，ismagnificentinitssilkywhiteness，ontheoutside；inside，itisadisgustingcesspit。Thecolonyremainsinitalldayandforthegreaterpartofthenight。
Itsalliesforthinprocessiononlyinthelatehoursoftwilight，tobrowseupontheadjacentfoliage。Thislonginternmentleadstoaconsiderableaccumulationofdroppingsintheheartofthedwelling。
Fromallthethreadsofthislabyrinthhangchapletsofthesedroppings；
thewallsareupholsteredwiththeminallthecorridors；thelittlenarrowchambersareencumberedwiththem。Fromanestthesizeofaman’sheadIhaveobtained，withasieve，overthree-quartersofapintofstercoralpellets。
Nowitisinthemidstofthisordurethatthecaterpillarsliveandhavetheirbeing；inthemidstofittheymove，swarmandsleep。Theresultsofthisuttercontemptfortherulesofcleanlinessareobvious。Certainly，theProcessionarydoesnotsoilhiscoatbycontactwiththosedrypellets；
heleaveshishomewithhiscostumeneatandglossy，suggestingnotasuspicionofuncleanliness。Nomatter:byconstantlyrubbingagainstthedroppings，hisbristlesareinevitablysmearedwithvirusandtheirbarbspoisoned。
Thecaterpillarbecomesirritant，becausehismanneroflifesubjectshimtoprolongedcontactwithhisownordure。
NowconsidertheHedgehogCaterpillar。Whyisheharmless，despitehisfierceandhirsuteaspect？Becausehelivesinisolationandisalwaysonthemove。Hismane，aptthoughitbetocollectandretainirritantparticles，willnevergiveustheitch，forthesimplereasonthatthecaterpillardoesnotlieonhisexcretions。Distributedalloverthefieldsandfarfromnumerous，owingtothecaterpillar’ssolitaryhabits，thedroppings，thoughpoisonous，cannottransfertheirpropertiestoafleecewhichdoesnotcomeintocontactwiththem。IftheHedgehoglivedinacommunity，inanestservingasacesspit，hewouldbetheforemostofourstingingcaterpillars。
Atfirstsight，thebarrack-roomsoftheSilkworm-nurseriesseemtofulfiltheconditionsnecessarytothesurfacevenomoftheworms。Eachchangeoflitterresultsintheremovalofbasketfulsofdroppingsfromthetrays。Overthisheaped-uporduretheSilk-wormsswarm。Howisitthattheydonotacquirethepoisonouspropertiesoftheirownexcrement？
Iseetworeasons。Inthefirstplace，theyarehairless；andabrushlikecoatmaywellbeindispensabletothecollectionofthevirus。Inthesecondplace，farfromlyinginthefilth，theyliveabovethesoiledstratum，beinglargelyseparatedfromitbythebedofleaves，whichisrenewedseveraltimesaday。Despitecrowding，thepopulationofatrayhasnothingthatcanbecomparedwiththeordinaryhabitsoftheProcessionary；andsoitremainsharmless，inspiteofitsstercoraltoxin。
Thesefirstenquiriesleadustoconclusionswhichthemselvesareveryremarkable。Allcaterpillarsexcreteanurticatingmatter，whichisidenticalthroughouttheseries。But，ifthepoisonistomanifestitselfandtocauseusthatcharacteristicitching，itisindispensablethatthecaterpillarshalldwellinacommunity，spendinglongperiodsinthenest，asilkenbagladenwithdroppings。Thesefurnishthevirus；thecaterpillar’shairscollectitandtransferittous。
Thetimehascometotackletheproblemfromanotherpointofview。
Isthisformidablematterwhichalwaysaccompaniestheexcretionsadigestiveresiduum？Isitnotratheroneofthosewastesubstanceswhichtheorganismengenderswhileatwork，wastesubstancesdesignatedbythegeneralappellationofurinaryproducts？
Toisolatetheseproducts，tocollectthemseparately，wouldscarcelybepracticable，ifwedidnothaverecoursetowhatfollowsonthemetamorphosis。
EveryMoth，onemergingfromherchrysalis，rejectsacopiousmixtureofuricacidandvarioushumoursofwhichverylittleisasyetknown。Itmaybecomparedwiththebrokenplasterofabuildingrebuiltonanewplanandrepresentstheby-productsofthemightylaboursaccomplishedinthetransfiguredinsect。Theseremainsareessentiallyurinaryproducts，withnoadmixtureofdigestedfoodstuffs。
TowhatinsectshallIapplyforthisresiduum？Chancedoesmanythings。
Icollect，fromtheoldelm-treeinthegarden，aboutahundredcuriouscaterpillars。Theyhavesevenrowsofpricklesofanamberyellow，asortofbushwithfourorfivebranches。IshalllearnfromtheButterflythattheybelongtotheGreatTortoiseshellVanessapolychloros，LIN。。
Rearedonelm-leavesunderawire-gauzecover，mycaterpillarsundergotheirtransformationtowardstheendofMay。Theirchrysalidsarespeckedwithbrownonawhitishgroundanddisplayontheundersurfacesixradiantsilveryspots，asortofdecorativetinsel，likesomanymirrors。Fixedbythetailwithasilkenpad，theyhangfromthetopofthedome，swingingattheleastmovementandemittingvividflashesoflightfromtheirreflectors。Mychildrenareamazedatthislivingchandelier。
ItisatreatforthemwhenIallowthemtocomeandadmireitinmyanimalstudio。
Anothersurpriseawaitsthem，thistimeatragicone，however。Afortnightlater，theButterfliesemerge。Ihaveplacedunderthecoveralargesheetofwhitepaper，whichwillreceivethedesiredproducts。Icallthechildren。
Whatdotheyseeonthepaper？
Largespotsofblood。Undertheirveryeyes，fromupthere，atthetopofthedome，abutterflyletsfallagreatreddrop:plop！Nojoyforthechildrento-day；anxietyrather，almostfear。
Isendthemaway，sayingtothem:
\"Besureandremember，kiddies，whatyouhavejustseen；and，ifeveranyonetalkstoyouaboutshowersofblood，don’tbesillyandfrightened。
AprettyButterflyisthecauseofthoseblood-redstains，whichhavebeenknowntoterrifycountry-folk。Themomentsheisborn，shecastsout，intheformofaredliquid，theremainsofheroldcaterpillarbody，abodyremodelledandreborninabeautifulshape。Thatisthewholesecret。\"
Whenmyartlessvisitorshavedeparted，Iresumemyexaminationoftherainofbloodfallingunderthecover。Stillclingingtotheshellofitschrysalis，eachTortoiseshellejectsandshedsuponthepaperagreatreddrop，which，ifleftstanding，depositsapowderypinksediment，composedofurates。Theliquidisnowadeepcrimson。
Whenthewholethingisperfectlydry，Icutoutofthespottedpapersomeofthericherstainsandsteepthebitsinether。Thespotsonthepaperremainasredasattheoutset；andtheliquidassumesalightlemontint。Whenreducedbyevaporationtoafewdrops，thisliquidprovidesmewithwhatIrequiretosoakmysquareofblotting-paper。
WhatshallIsaytoavoidrepeatingmyself？TheeffectsofthenewcausticarepreciselythesameasthosewhichIexperiencedwhenIusedthedroppingsoftheProcessionary。Thesameitching，thesameburning，thesameswellingwiththefleshthrobbingandinflamed，thesameserousexudation，thesamepeelingoftheskin，thesamepersistentredness，whichlingersforthreeorfourmonths，longaftertheulcerationitselfhasdisappeared。
Withoutbeingverypainful，thesoreissoirksomeandabovealllookssouglythatIswearnevertoletmyselfinforitagainHenceforth，withoutwaitingforthethingtoeatintomyflesh，IshallremovethecaterpillarplasterassoonasIfeelaconclusiveitching。
Inthecourseofthesepainfulexperiences，friendsupbraidmewithnothavingrecoursetotheassistanceofsomeanimal，suchastheGuinea-pig，thatstockvictimofthephysiologists。ItakenonoteoftheirreproachesTheanimalisastoic。Itsaysnothingofitssufferings。If，thetorturebeingalittletoointense，itcomplains，Iaminnopositiontointerpretitscriesexactlyortoattributethemtoadefiniteimpression。TheGuinea-pigwillnotsay:
\"Itsmarts，ititches，itburns。\"
Hewillsimplysay:
\"Thathurts。\"
AsIwanttoknowthedetailsofthesensationsexperienced，thebestthingistoresorttomyownskin，theonlywitnessonwhoseevidenceI
canrelyimplicitly。
Attheriskofprovokingasmile，Iwillventureonanotherconfession。
AsIbegintoseeintothemattermoreclearly，IhesitatetotortureordestroyasinglecreatureinGod’sgreatcommunity。Thelifeoftheleastoftheseisathingtoberespected。Wecantakeitaway，butwecannotgiveit。Peacetothoseinnocents，solittleinterestedinourinvestigations！
Whatdoesourrestlesscuriositymattertotheircalmandsacredignorance？
Ifwewishtoknow，letuspaythepriceourselvesasfaraspossible。
Theacquisitionofanideaiswellworththesacrificeofabitofskin。
TheElmTortoiseshell，withherrainofblood，mayleaveustoacertainextentindoubt。Mightnotthisstrangeredsubstance，withitsunusualappearance，containapoisonwhichislikewiseexceptional？IaddressmyselfthereforetotheMulberryBombyx，tothePineBombyxandtotheGreatPeacock。
IcollecttheuricexcretionsejectedbythenewlyhatchedMoths。
Thistime，theliquidiswhitish，sulliedhereandtherewithuncertaintints。Thereisnoblood-redcolouration；buttheresultisthesame。Thevirulentenergymanifestsitselfinthemostdefinitemanner。ThereforetheProcessionary’svirusexistsequallyinallcaterpillars，inallButterfliesandMothsemergingfromthechrysalis；andthisvirusisabyproductoftheorganism，aurinaryproduct。
Thecuriosityofourmindsisinsatiable。Themomentareplyisobtained，afreshquestionarises。WhyshouldtheLepidopteraalonebeendowedinthismanner？Theorganiclaboursaccomplishedwithinthemcannotdiffergreatly，astothenatureofthematerials，fromthosepresidingoverthemaintenanceoflifeinotherinsects。There。foretheseothersalsoelaborateaby-productwhichhasstingingpowers。Thiscanbeverified-andthatforthwith-withtheelementsatmydisposal。
ThefirstreplyisfurnishedbyCetoniafloricola，ofwhichBeetleIcollecthalfadozenchrysalidsfromaheapofleaveshalf-convertedintomould。Aboxreceivesmyfind，laidonasheetofwhitepaper，onwhichtheurinaryfluidoftheperfectinsectwillfallassoonasthecasketsarebroken。TheweatherisfavourableandIhavenotlongtowait。Thethingisdone:thematterrejectediswhite，theusualcolouroftheseresidua，inthegreatmajorityofinsects，atthemomentofthemetamorphosis。Thoughbynomeansabundant，itneverthelessprovokesonmyfore-armaviolentitching，togetherwithmortificationoftheskin，whichcomesoffinflakes。ThereasonwhyitdoesnotdisplayamoredistinctsoreisthatIjudgeditprudenttoendtheexperiment。
Theburninganditchingtellmeenoughastotheresultsofacontactundulyprolonged。
NowtotheHymenoptera。Ihavenotinmypossession，Iregrettosay，anyofthosewithwhommyrearing-chambersusedformerlytoprovideme，whetherHoney-beeorHuntingWasps。IhaveonlyaGreenSaw-fly，whoselarvalivesinnumerousfamiliesontheleavesofthealder。Rearedundercover，thislarvaprovidesmewithenoughtinyblackdroppingstofillathimble。Thatissufficient:theurticationisquitedefinite。
Itakenexttheinsectswithincompletetransformations。
MyrecentrearingshavegivenmequiteacollectionofexcretionsemanatingfromtheOrthoptera。IconsultthoseoftheVineEphippiger[note2]andtheGreatGreyLocust。Bothstingtoadegreewhichoncemoremakesmeregretmylavishhand。
Wewillbesatisfiedwiththis；indeedmyarmsdemandasmuch，for，tattooedwith，redsquares，theyrefusetomakeroomforfreshbrandings。
Theexamplesaresufficientlyvariedtoimposethefollowingconclusion:
theProcessionary’svirusisfoundinahostofotherinsects，apparentlyevenintheentireseries。Itisaurinaryproductinherentintheentomologicalorganism。
Thedejectionsofinsects，especiallythoseevacuatedattheendofthemetamorphosis，containorareevenalmostentirelycomposedofurates。
Canthestingingmaterialbetheinevitableassociateofuricacid？Itshouldthenformpartoftheexcrementofthebirdandthereptile，whichinbothcasesisveryrichinurates。Hereagainisasuspicionworthyofverificationbyexperiment。
Forthemomentitisimpossibleformetoquestionthereptile；itiseasy，ontheotherhand，tointerrogatethebird，whosereplywillsuffice。Iacceptwhatisofferedbychance:aninsectivorousbird，theSwallow，andagraminivorousbird，theGoldfinch。Well，theirurinarydejections，whencarefullyseparatedfromthedigestiveresidua，havenottheslighteststingingeffect。Thevirusthatcausesitchingsindependentthereforeofuricacid。Itaccompaniesitintheinsectclass，withoutbeingitsinvariableconcomitanteveryelsewhere。
Alaststepremainsforustotake，namely，toisolatethestingingelementandtoobtainitinquantitiespermittingofpreciseenquiriesintoitsnatureandproperties。Itseemstomethatmedicalsciencemightturntoaccountamaterialwhoseenergyrivalsthatofcantharides，ifitdoesnotexceedit。Thequestionappealstome。Iwouldgladlyreturntomybelovedchemistry；butIshouldwantreagents，apparatus，alaboratory，awholecostlyarsenalofwhichImustnotdream，afflictedasIamwithaterribleailment:impecuniosity，thesearcher’shabituallot。
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[note1]:ABacon-beetle——Translator’sNote。
[note2]:AspeciesofGrasshopper——Translator’sNote。9，TheLifeoftheCaterpillar，byJ。HenriFabre，1916TheLifeoftheCaterpillar，byJ。HenriFabre，1916IX:THEPSYCHES:THELAYING
INTHEspringtime，oldwallsanddustyroadsharbourasurpriseforwhosohaseyestosee。Tinyfaggots，fornoapparentreason，setthemselvesinmotionandmaketheirwayalongbysuddenjerks。Theinanimatecomestolife，theimmovablestirs。Howdoesthiscomeabout？Lookcloserandthemotivepowerwillstandrevealed。
Enclosedwithinthemovingbundleisafairlywell-developedcaterpillar，prettilystripedinblackandwhite。Seekingforfoodorperhapsforaspotwherethetransformationcanbeeffected，hehurriesalongtimidly，attiredinaqueerrig-outoftwigsfromwhichnothingemergesexcepttheheadandthefrontpartofthebody，whichisfurnishedwithsixshortlegs。Attheleastalarmhegoesrightinanddoesnotbudgeagain。Thisisthewholesecretofthelittleroamingbundleofsticks。
ThefaggotcaterpillarbelongstothePsychegroup，whosenameconveysanallusiontotheclassicPsyche，symbolicalofthesoul。Wemustnotallowthisphrasetocarryourthoughtstoloftierheightsthanisfitting。Thenomenclator，withhisrathercircumscribedviewoftheworld，didnottroubleaboutthesoulwheninventinghisdescriptivelabel。Hesimplywantedaprettyname；andcertainlyhecouldhavehitonnothingbetter。
Toprotecthimselffromtheweather，ourchilly，bare-skinnedPsychebuildshimselfaportableshelter，atravellingcottagewhichtheownerneverleavesuntilhebecomesaMoth。Itissomethingbetterthanahutonwheelswithathatchedrooftoit:itisahermit’sfrock，madeofanunusualsortoffrieze。InthevalleyoftheDanubethepeasantwearsagoatskincloakfastenedwithabeltofrushes。ThePsychedonsanevenmorerusticapparel。Hemakeshimselfasuitofclothesoutofhop-poles。
Itistruethat，beneaththisrudeconglomeration，whichwouldbearegularhair-shirttoaskinasdelicateashis，heputsathickliningofsilk。
TheClythraBeetlegarbshimselfinpottery；thisonedresseshimselfinafaggot。
InApril，onthewallsofmychiefobservatory，thatfamouspebblyacrewithitswealthofinsectlife，IfindthePsychewhoistofurnishmewithmymostcircumstantialanddetailedrecords。[note1]Heisatthisperiodinthetorporoftheapproachingmetamorphosis。
Aswecanaskhimnothingelseforthemoment，letuslookintotheconstructionandcompositionofhisfaggot。
Itisanotirregularstructure，spindle-shapedandaboutaninchandahalflong。Thepiecesthatcomposeitarefixedinfrontandfreeattheback，arearrangedanyhowandwouldformaratherineffectiveshelteragainstthesunandrainifthereclusehadnootherprotectionthanhisthatchedroof。
ThewordthatchissuggestedtomymindbyasummaryinspectionofwhatIsee，butitisnotanexactexpressioninthiscase。Onthecontrary，graminaceousstrawsarerare，tothegreatadvantageofthefuturefamily，which，asweshalllearnpresently，wouldfindnothingtosuittheminjointedplanks。Whatpredominatesisremnantsofverysmallstalks，light，softandrichinpith，suchasarepossessedbyvariousChicoriaceae。I
recognizeinparticularthefloralstemsofthemouse-earhawkweedandtheNimespterotheca。Nextcomebitsofgrass-leaves，scalytwigsprovidedbythecypress-treeandallsortsoflittlesticks，coarsematerialsadoptedforthelackofany-thingbetter。Lastly，ifthefavouritecylindricalpiecesfallshort，themantleissometimesfinishedoffwithanampleflouncedtippet，thatistosay，withfragmentsofdryleavesofanykind。
Incompleteasitis，thislistshowsusthatthecaterpillarapartfromhispreferenceforpithymorsels，hasnoveryexclusivetastes。Heemploysindifferentlyanythingthathecomesupon，providedthatitbelight，verydry，softenedbylongexposuretotheairandofsuitabledimensions。Allhisfinds，iftheycomeanywherenearhisestimates，areusedjustastheyare，withoutanyalterationsorsawingtoreducethemtotheproperlength。
ThePsychedoesnottrimthelathsthatgotoformhisroof；hegathersthemashefindsthem。Hisworkislimitedtoimbricatingthemoneaftertheotherbyfixingthematthefore-end。
Inordertolenditselftothemovementsofthejourneyingcaterpillarandinparticulartofacilitatetheactionoftheheadandlegswhenanewpieceistobeplacedinposition，thefrontpartofthesheathrequiresaspecialstructure。Hereacasingofbeamsisnolongerallowable，fortheirlengthandstiffnesswouldhampertheartisanandevenmakehisworkimpossible；whatisessentialhereisaflexibleneck，abletobendinalldirections。Theassemblageofstakesdoes，infact，endsuddenlyatsomedistancefrom。thefore-partandistherereplacedbyacollarinwhichthesilkenwoofismerelyhardenedwithverytinyligneousparticles，tendingtostrengthenthematerialwithoutimpairingitsflexibility。Thiscollar，whichgivesfreemovement，issoimportantthatallthePsychesmakeequaluseofit，howevermuchtherestoftheworkmaydiffer。Allcarry，infrontofthefaggotofsticks，ayieldingneck，softtothetouch，formedinsideofawebofpuresilkandvelvetedoutsidewithafinesawdustwhichthecaterpillarobtainsbycrushingwithhismandiblesanysortofdrystraw。
Asimilarvelvet，butlustrelessandfaded，apparentlythroughage，finishesthesheathattheback，intheformofaratherlong，bareappendix，openattheend。
Letusnowremovetheoutsideofthestrawenvelope，shreddingitpiecemeal。
Thedemolitiongivesusavaryingnumberofjoists:Ihavecountedasmanyaseightyandmore。Theruinthatremainsisacylindricalsheathwhereinwediscover，fromoneendtotheother，thestructurewhichweperceivedatthefrontandrear，thetwopartswhicharenaturallybare。Thetissueeverywhereisofverystoutsilk，whichresistswithoutbreakingwhenpulledbythefingers，asmoothtissue，beautifullywhiteinside，drabandwrinkledoutside，whereitbristleswithencrustedwoodyparticles。
Therewillbeanopportunitylatertodiscoverbywhatmeansthecaterpillarmakeshimselfsocomplicatedagarment，inwhicharelaidoneupontheother，inadefiniteorder，first，theextremelyfinesatinwhichisindirectcontactwiththeskin；next，themixedstuff，asortoffriezedustedwithligneousmatter，whichsavesthesilkandgivesconsistencytothework；lastly，thesurtoutofoverlappinglaths。
Whileretainingthisgeneralthreefoldarrangement，thescabbardoffersnotablevariationsofstructuraldetailinthedifferentspecies。
Here，forinstance，isasecondPsyche，[note2]themostbelatedofthethreewhichIhavechancedtocomeupon。
ImeethimtowardstheendofJune，hurryingacrosssomedustypathnearthehouses。Hiscasessurpassthoseofthepreviousspeciesbothinsizeandinregularityofarrangement。Theyformathickcoverlet，ofmanypieces，inwhichIrecognizeherefragmentsofhollowstalks，therebitsoffinestraw，withperhapsstrapsformedofbladesofgrass。Infrontthereisneveranymantillaofdeadleaves，atroublesomepieceoffinerywhich，withoutbeinginregularuse，isprettyfrequentinthecostumeofthefirst-namedspecies。Attheback，nolong，denudedvestibule。Savefortheindispensablecollarattheaperture，alltherestiscasedinlogs。
Thereisnotmuchvarietyaboutthething，but，whenallissaid，thereisacertaineleganceinitssternfaultlessness。
Thesmallestinsizeandsimplestindressisthethird，[note3]whoisverycommonattheendofwinteronthewalls，aswellasinthefurrowsofthebarksofgnarledoldtrees，betheyolive-trees，holm-oaks，elmsoralmostanyother。Hiscase，amodestlittlebundle，ishardlymorethantwo-fifthsofaninchinlength。Adozenrottenstraws，gleanedatrandomandfixedclosetooneanotherinaparalleldirection，represent，withthesilksheath，hiswholeoutlayondress。Itwouldbedifficulttoclotheone’sselfmoreeconomically。