Inafewdays，thetubeswarmingwithnewbornvermincontainsaliquidasfluidandtransparentaswater。NotadropwouldremaininthetubeifIturneditupsidedown。Allthewhiteofegghasdisappeared，liquefied。Asfortheworms，whicharealreadyafairsize，theyseemveryillatease。Deprivedofasupportwhencetoattaintheouterair，mostofthemdiveintothebrothoftheirownmaking，wheretheyperishbydrowning。Others，endowedwithgreatervigor，crawluptheglasstotheplugandmanagetomaketheirwaythroughthewadding。Theirpointedfront，armedwithgrapplingirons，isthenailthatpenetratesthefibrousmass。
Intheothertest—tube，standingbesidethefirstandsubjectedtothesameatmosphericinfluences，nothingstrikinghasoccurred。
Thehard—boiledwhiteofegghasretaineditsdeadwhitecoloranditsfirmness。IfinditasIleftit。TheutmostthatIobserveisafewtracesofmust。Theresultofthisfirstexperimentispatent:theBluebottle’sgrubisthemediumthatconvertscoagulatedalbumenintoaliquid。
Thevalueofchemist’spepsinisestimatedbythequantityofhard—
boiledwhiteofeggwhichagramofthatagentcanliquefy。Themixturehastobeexposedinanoventoatemperatureof1400F。
andalsotobefrequentlyshaken。Mypreparation，inwhichthebluebottle’seggsarehatched，isneithershakennorsubjectedtotheheatofanoven;everythinghappensinquietnessandunderthethermometricconditionsofthesurroundingair;nevertheless，inafewdays，thecoagulatedalbumen，treatedbythevermin，runslikewater。
Thereagentthatcausesthisliquefactionescapesmyendeavorstodetectit。Thewormsmustdisgorgeitininfinitesimaldoses，whilethespikesintheirthroats，whichareincontinualmovement，emergealittlewayfromthemouth，reenterandreappear。Thosepistonthrusts，thosequasi—kisses，areaccompaniedbytheemissionofthesolvent:atleast，thatishowIpictureit。Themaggotspitsonitsfood，placesonitthewherewithaltomakeitintobroth。Toappraisethequantityofthematterexpectoratedisbeyondmypowers:Iobservetheresult，butdonotperceivetheleaveningagent。
Well，thisresultisreallyastounding，whenweconsiderthescantinessofthemeans。Nopig’sorsheep’spepsincanrivalthatoftheworm。IhaveabottleofpepsinthatcomesfromtheSchoolofChemistryatMontpellier。Ilavishlypowdersomepiecesofhard—boiledwhiteofeggwiththepotentdrug，justasIdidwiththeeggsoftheBluebottle。Theovenisnotbroughtintoplay，neitherisdistilledwateradded，norhydrochloricacid:twoauxiliarieswhicharerecommended。Theexperimentisconductedinexactlythesamewayasthatofthetubeswiththevermin。TheresultisentirelydifferentfromwhatIexpected。Thewhiteofeggdoesnotliquefy。Itsimplybecomesmoistonthesurface;andeventhismoisturemaycomefromthepepsin，whichishighlyabsorbent。Yes，Iwasright:ifthethingwerefeasible，itwouldbeanadvantageforthechemiststocollecttheirdigestivedrugfromthestomachofthemaggot。Theworm，inthiscase，beatsthepigandthesheep。
Thesamemethodisfollowedfortheremainingexperiments。Iputthebluebottle’seggstohatchonapieceofmeatandleavethewormstodotheirworkastheyplease。Theleantissues，whetherofmutton，beeforpork，nomatterwhich，arenotturnedintoliquid;theybecomeapeasoupofaclaretybrown。Theliver，thelung，thespleenareattackedtobetterpurpose，without，however，gettingbeyondthestateofasemi—fluidjam，whicheasilymixeswithwaterandevenappearstodissolveinit。Thebrainsdonotliquefyeither:theysimplymeltintoathingruel。
Ontheotherhand，fattysubstances，suchasbeefsuet，lardandbutter，donotundergoanyappreciablechange。Moreover，thewormssoondwindleaway，incapableofgrowing。Thissortoffooddoesnotsuitthem。Why？Apparentlybecauseitcannotbeliquefiedbythereagentdisgorgedbytheworms。Inthesameway，ordinarypepsindoesnotattackfattysubstances;ittakespancreatintoreducethemtoanemulsion。Thiscuriousanalogyofproperties，positiveforalbuminous，negativeforfattymatter，proclaimsthesimilarityandperhapstheidentityofthedissolventdischargedbythegrubsandthepepsinofthehigheranimals。
Hereisanotherproof:theusualpepsindoesnotdissolvetheepidermis，whichisamaterialofahornynature。Thatofthemaggotsdoesnotdissolveiteither。IcaneasilyrearbluebottlegrubsondeadcricketswhosebelliesIhavefirstopened;butIdonotsucceedifthemorselbeleftintact:thewormsareunabletoperforatethesucculentpaunch;theyarestoppedbythecuticle，onwhichtheirreagentrefusestoact。OrelseIgivethemfrogs’
hindlegs，strippedoftheirskin。Thefleshturnstobrothanddisappearstothebone。IfIdonotpeelthelegs，theyremainintactinthemidstofthevermin。Theirthinskinissufficienttoprotectthem。
Thisfailuretoactupontheepidermisexplainswhythebluebottleatworkontheanimaldeclinestolayhereggsonthefirstpartthatcomeshandy。Sheneedsthedelicatemembraneofthenostrils，eyesorthroat，orelsesomewoundinwhichthefleshislaidbare。
Nootherplacesuitsher，howeverexcellentforflavoranddarkness。Atmost，findingnothingbetterwhenmystratagemsinterfere，shepersuadesherselftodabafeweggsundertheaxillaofapluckedbirdorinthegroin，twopointsatwhichtheskinisthinnerthanelsewhere。
Withhermaternalforesight，thebluebottleknowstoperfectionthechoicesurfaces，theonlyonesliabletosoftenandrunundertheinfluenceofthereagentdribbledbythenewborngrubs。Thechemistryofthefutureisfamiliartoher，thoughshedoesnotuseitforherownfeeding;motherhood，thatgreatinspirerofinstinct，teachesherallaboutit。
Scrupulousthoughshebeinchoosingexactlywheretolayhereggs，thebluebottledoesnottroubleaboutthequalityoftheprovisionsintendedforherfamily’sconsumption。Anydeadbodysuitsherpurpose。Redi，theItalianscientistwhofirstexplodedtheold，foolishnotionofwormsbegottenofcorruption，fedthevermininhislaboratorywithmeatofverydifferentkinds。Inordertomakehisteststhemoreconclusive，heexaggeratedthelargessofthedininghall。Thedietwasvariedwithtigerandlionflesh，bearandleopard，foxandwolf，muttonandbeef，horseflesh，donkeyfleshandmanyothers，suppliedbytherichmenagerieofFlorence。
Thiswastefulnesswasunnecessary:wolfandmuttonareallthesametoanunprejudicedstomach。
Adistantdiscipleofthemaggot’sbiographer，IlookattheprobleminalightwhichRedineverdreamtof。Anyfleshofoneofthehigheranimalssuitsthefly’sfamily。Willitbethesameifthefoodsuppliedbeofalowerorganismandconsistoffish，forinstance，offrog，mollusk，insect，centipede？Willthewormsaccepttheseviandsand，aboveall，cantheymanagetoliquefythem，whichisthefirstandforemostcondition？
Iserveapieceofrawwhiting。Thefleshiswhite，delicate，partlytranslucent，easyforourstomachstodigestandnolesssuitedtothegrub’sdissolvent。Itturnsintoanopalescentfluid，whichrunslikewater。Infact，itliquefiesinmuchthesamewayashard—boiledwhiteofegg。Thewormsatfirstwaxfat，aslongastheconditionsallowofsomesolideyotsremaining;
then，whenfootholdfails，threatenedwithdrowninginthetoofluidbroth，theycreepupthesideoftheglass，anxiousandrestlesstobeoff。Theyclimbtothecotton—woolstopperofthetest—tubeandtrytoboltthroughthewadding。Endowedwithstubbornperseverance，nearlyallofthemdecampinspiteoftheobstacle。Thetest—tubewiththewhiteofeggshowedmeasimilarexodus。Althoughthefaresuitsthem，astheirgrowthwitnesses，thewormsceasefeedingandmakeapointofescapingwhendeathbydrowningisimminent。
Withotherfish，suchasskateandsardines，withthefleshoffrogsandtreefrogs，themeatsimplydissolvesintoaporridge。
Hashesofslug，Scolopendraorprayingmantisfurnishthesameresult。
Inallthesepreparations，thedissolvingagentofthewormsisasmuchinevidenceaswhenbutcher’smeatisemployed。Moreover，thegrubsseemsatisfiedwiththequeerdishwhichmycuriosityprescribesforthem;theythriveamidstthevictualsandundergotheirtransformationintopupae。
Theconclusion，therefore，ismuchmoregeneralthanRediimagined。
Anymeat，nomatterwhetherofahigherorlowerorder，suitsthebluebottleforthesettlementofherfamily。Thecarcassesoffurredandfeatheredanimalsarethefavoritevictuals，probablybecauseoftheirrichness，whichallowsofplentifullayings;but，shouldtheoccasiondemandit，theothersarealsoaccepted，withoutinconvenience。Anycarrionthathaslivedthelifeofananimalcomeswithinthedomainofthesescavengers。
Whatistheirnumbertoonemother？Ihavealreadyspokenofadepositofthreehundred，countedeggbyegg。Aquitefortuitouscircumstanceenabledmetogomuchfarther。InthefirstweekofJanuary1905，weexperiencedasuddenshortcoldsnapofaseverityveryexceptionalinmypartofthecountry。Thethermometerfelltotwelvedegreesbelowzero。Whileafiercenorthwindwasragingandbeginningtoreddentheleavesoftheolivetrees，cameoneandbroughtmeabarnorscreechowl，whichhehadfoundontheground，exposedtotheair，notfarfrommyhouse。MyreputationasaloverofanimalsmadethedonorbelievethatIshouldbepleasedwithhisgift。
Iwas，asamatteroffact，butforreasonswhereofthefindercertainlyneverdreamt。Theowlwasuntouched，withtrimfeathersandnottheleastwoundthatshowed。Perhapshehaddiedofcold。
Whatmademegratefullyacceptthepresentwasexactlythatwhichwouldhaveinclinedanyonebutmyselftorefuseit。Theowl’seyes，glazedindeath，werehiddenunderathickmassofeggs，whichIrecognizedasabluebottle’s。Similarmassesoccupiedthevicinityofthenostrils。IfIwantedmaggots，here，ofacertainty，wasarichercropthanIhadeverbeheld。
Iplacethecorpseonthesandofapan，withawiregauzecover，andleaveeventstotaketheircourse。ThelaboratoryinwhichI
installmybirdisnoneotherthanmystudy。Itisascoldinthere，ornearly，asoutside，somuchsothatthewaterintheaquariuminwhichIusedtorearcaddiswormshasfrozenintoasolidblockofice。Undertheseconditionsoftemperature，theowl’seyeskeeptheirwhiteveilofgermsunchanged。Nothingstirs，nothingswarms。Wearyofwaiting，Ipaynomoreattentiontothecarcass;Ileavethefuturetodecidewhetherthecoldhasexterminatedthefly’sfamilyornot。
BeforetheendofMarch，thepacketsofeggshavedisappeared，I
knownothowlong。Thebird，forthatmatter，seemstobeintact。
Ontheventralsurface，whichisturnedtotheair，thefeatherskeeptheirsmootharrangementandtheirfreshcoloring。Iliftthething。Itislight，verydryandgivesahardsound，likeanoldshoetannedbythesummersuninthefields。Thereisnosmell。
Thedrynesshasvanquishedthestench，which，inanycase，wasneveroffensiveduringthattimeoffrost。Ontheotherhand，theback，whichtouchedthesand，isaloathsomewreck，partlydeprivedofitsfeathers。Thequillsofthetailarebarebarreled;afewwhitenedbonesshow，deprivedoftheirmuscles。Theskinhasturnedintoadarkleather，piercedwithroundholeslikethoseofasieve。Itisallhideouslyugly，butmostinstructive。
Thewretchedowl，withhisshatteredbackbone，teachesus，firstofall，thatatemperaturetwelvedegreesoffrostdoesnotendangertheexistenceofthebluebottle’sgerms。Thewormswerebornwithoutaccident，despitetherudeblast;theyfeastedcopiouslyonextractofmeat;then，growingbigandfat，theydescendedintotheearthbypiercingroundholesinthebird’sskin。Theirpupaemustnowbeinthesandofthepan。
Theyare，inpointoffact，andinsuchnumbersthatIhavetoresorttosiftinginordertocollectthem。IfIusedtheforceps，Ishouldneverhavedonesortingsogreataquantity。Thesandpassesthroughthemeshesofthesieve，thepupaeremainabove。Tocountthemwouldwearoutmypatience。Imeasurethembythebushel，thatistosay，withathimbleofwhichIknowtheholdingcapacityinpupae。Theresultofmycalculationisnotfarshortofninehundred。
Doesthisfamilyproceedfromonemother？Iamquitereadytoadmitit，sounlikelyisitthatthebluebottle，whoissorareinsideourhousesduringtheseverecoldofwinter，shouldbefrequentenoughoutsidetoformintogroupsandtodobusinessincommonwhileanicyblastisraging。Abelatedspecimen，theplaythingofthenorthwind，andonealonemusthavedepositedtheburdenofherovariesontheowl’seyes。Thislayingofninehundredeggs，anincompletelayingperhaps，bearswitnesstothemightypartplayedbytheflyasaliquidatorofcorpses。
Beforethrowingawaythescreechowltreatedbytheworms，letusovercomeourrepugnanceandgiveaglanceinsidethebird。Weseeatortuouscavity，fencedinbynamelessruins。Musclesandbowelshavedisappeared，convertedintobrothandgraduallyconsumedbytheteemingthrong。Ineverypart，whatwaswethasbecomedry，whatwassolidmuddy。Invainmyforcepsransackseverynookandcorner:itdoesnothituponasinglepupa。Allthewormshaveemigrated，all，withoutexception。Fromfirsttolast，theyhaveforsakentherefugeofthecorpse，sosofttotheirdelicateskins;
theyhaveleftthevelvetforthehardground。Isdrynessnecessarytothematthisstage？Theyhaditinthecarcass，whichwasthoroughlydrained。Wouldtheyprotectthemselvesagainstthecoldandrain？Nosheltercouldsuitthembetterthanthethickquiltofthefeathers，whichhasremainedwhollyundamagedonthebelly，thebreastandeverypartthatwasnotintouchwiththeground。Itlooksasthoughtheyhadfledfromcomforttoseekalesskindlydwellingplace。Whenthehouroftransformationcame，alllefttheowl，thatmostexcellentlodging;alldivedintothesand。
Theexodusfromthemortuarytabernaclewasmadethroughtheroundholeswherewiththeskinispierced。Thoseholesaretheworms’
work:ofthatthereisnodoubt;andyetwehavelatelyseenthemothersrefuseasabedfortheireggsanypartwhereatthefleshisprotectedbyaskinofsomethickness。Thereasonisthefailureofthepepsintoactonepidermicsubstances。Intheabsenceofliquefactionatsuchpoints，thenourishinggruelisunprocurable。Ontheotherhand，thetinywormsarenotable——oratleastdonotknowhow——todigthroughtheintegumentwiththeirpairofgutturalharpoons，torenditandreachtheliquefiableflesh。Thenewbornlackstrengthand，aboveall，purpose。But，asthetimecomesfordescendingintotheearth，theworms，nowpowerfulandsuddenlyversedinthenecessaryart，wellknowhowtoeatawaypatientlyandclearthemselvesapassage。Withthehooksoftheirspikestheydig，scratchandtear。Instincthasflashesofinspiration。Whattheanimaldidnotknowhowtodoatthestartitlearnswithoutapprenticeshipwhenthetimecomestopracticethisorthatindustry。Themaggotripeforburialperforatesamembranousobstaclewhichthegrubintentuponitsbrothwouldnotevenhaveattemptedtoattackwitheitheritspepsinoritsgrapnels。
Whydoesthewormquitthecarcass，thatcapitalshelter？Whydoesitgoandtakeupitsabodeintheground？Astheleadingdisinfectorofdeadthings，itworksatthemostimportantmatter，thesuppressionoftheinfection;butitleavesaplentifulresiduum，whichdoesnotyieldtothereagentsofitsanalyticalchemistry。Theseremainshavetodisappearintheirturn。Afterthefly，anatomistscomehastening，whotakeupthedryrelic，nibbleskin，tendonsandligamentsandscrapethebonesclean。
ThegreatestexpertinthisworkistheDermestesbeetle，anenthusiasticgnawerofanimalremains。Soonerorlater，hewillcometothejointalreadyexploitedbythefly。Nowwhatwouldhappenifthepupaewerethere？Theanswerisobvious。TheDermestes，wholoveshardfood，woulddighisteethintothehornylittlekegsanddemolishthematabite。Eventhoughhedidnottouchthecontents，alivethingwhichheprobablydislikes，hewouldatleasttesttheflavorofthatlifelesssubstance，thecontainer。ThefutureFlywouldbelost，becausehercasingwouldbepierced。Evenso，inthestoreroomsofoursilkmills，acertainDermestes（Dermestesvulpinus，FABR。）digsintothecocoonstoattackthehornycoveringofthechrysalis。
Themaggotforeseesthedangerandmakesitselfscarcebeforetheotherarrives。Inwhatsortofmemorydoesithousesomuchwisdom，indigent，headlesscreaturethatitis，foritisonlybyextensionthatwecangivethenameofheadtotheanimal’spointedforepart？Howdiditlearnthat，tosafeguardthepupa，itmustdesertthecarcassandthat，tosafeguardthefly，itmustnotburyitselftoofardown？
Toemergefromundergroundaftertheperfectinsectishatched，thebluebottle’sdeviceconsistsindisjointingherheadintotwomovablehalves，which，eachdistendedwithitsgreatredeye，byturnsseparateandreunite。Intheinterveningspace，alarge，glassyherniarisesanddisappears，disappearsandrises。Whenthetwomoveasunder，withoneeyeforcedbacktotheright，theothertotheleft，itisasthoughtheinsectweresplittingitsbrainpaninordertoexpelthecontents。Thentheherniarises，bluntattheendandswollenintoagreatknob。Next，theforeheadclosesandtheherniaretreats，leavingvisibleonlyakindofshapelessmuzzle。Inshort，afrontalpouch，withdeeppulsationsmomentarilyrenewed，becomestheinstrumentofdeliverance，thepestlewherewiththenewlyhatchedbluebottlebruisesthesandandcausesittocrumble。Graduallythelegspushtherubbishbackandtheinsectadvancessomuchtowardthesurface。
Ahardtask，thisexhumationbydintoftheblowsofacleftandpalpitatinghead。Moreover，theexhaustingefforthastobemadeatthemomentofgreatestweakness，whentheinsectleavesthatprotectingcasket，itspupa。Itemergesfromitpale，flabbyandunsightly，sorrilycladinthewingswhich，foldedlengthwiseandmadeshorterbytheirscallopededge，onlyjustcoverthetopoftheback。Wildlybristlingwithhairsandcoloredashen—gray，itisapiteoussight。Thelargesetofwings，suitableforflight，willspreadlater。Forthemoment，itwouldonlybeinthewayamidtheobstaclestobepassedthrough。Lateralsowillcomethefaultlessdresswhereintheiridescentindigo—bluestandsoutagainsttheseverityoftheblack。
Thefrontalherniathatcrumblesthesandwithitsimpacthasatendencytomakeplayforsometimeaftertheemergencefromtheground。Takeholdwiththeforcepsofoneofthehindlegsofanewlyreleasedfly。Forthwith，theimplementoftheheadbeginstowork，swellingandsubsidingasenergeticallyasamomentago，whenithadtomakeaholeinthesand。Theinsect，hamperedinitsmovementsaswhenitwasunderground，strugglesasbestitcanagainsttheonlyobstaclethatitknows。Withitsheavingknob，itpoundstheairevenasbutnowitpoundedtheearthybarrier。Inallunpleasantcircumstances，itsoneresourceistocleaveitsheadandproduceitscranialhernia，whichmovesoutandin，inandout。Fornearlytwohours，interspersedwithhaltsduetofatigue，thelittlemachinekeepsthrobbinginmyforceps。
Inthemeantime，however，thedesperateoneishardeningherskin;
shespreadswidethesailofherwingsanddonsherdeepmourningofblackanddarkestblue。Thenhereyes，warpedsideways，cometogetherandresumetheirnormalposition。Thecleftforeheadcloses;thedeliveringblistergoesin，nevertoshowitselfagain。
Butthereisoneprecautiontobetakenfirst。Withitsfronttarsi，theinsectcarefullybrushesthebumpabouttodisappearfromview，lestgritshouldlodgeinthecraniumwhenthetwohalvesoftheheadarejoinedforgood。
Themaggotisawareofthetrialsthatawaititwhen，asafly，itwillhavetocomeupfromunderground;itknowsbeforehandhowdifficulttheascentwillbewiththefeebleinstrumentatitsdisposal，sodifficult，infact，astobecomefatalshouldthejourneybeatallprolonged。Itforeseesthedangersaheadofitandavertsthemaswellasitcan。Giftedwithtwoironshodsticksinitsthroat，itcaneasilydescendtosuchdepthsasitpleases。Theneedforgreaterquietandalesstryingtemperaturecallsforthedeepestpossiblehome:thelowerdownitis，thebetterforthewelfareofthewormandthepupa，onconditionthatdescentbepracticable。Itis，perfectly;andyet，thoughfreetoobeyitsinspiration，thegrubrefrains。Irearitinadeeppan，fulloffine，drysand，easytoexcavate。Theintermentnevergoesveryfar。Aboutahand’sbreadthisallthatthemostprogressivediggerventuresupon。Mostoftheinterredremainnearerstilltothesurface。Here，underathinlayerofsand，thegrub’sskinhardensandbecomesacoffin，acasket，whereinthetransformationsleepisslept。Afewweekslater，theburiedoneawakes，transfiguredbutweak，havingnaughtwherewithtounearthherselfbutthethrobbingherniaofheropenforehead。
Whatthemaggotdeniesitselfitisopentometorealize，shouldI
caretoknowthedepthwhencetheflyisabletomount。Iplacefifteenbluebottlepupae，obtainedinwinter，atthebottomofawidetubeclosedatoneend。Abovethepupaeisaperpendicularcolumnoffine，drysand，theheightofwhichvariesindifferenttubes。Aprilcomesandthehatchingbegins。
Atubewithsixcentimetersofsand，theshallowestofthecolumnsunderexperiment，yieldsthebestresult。Ofthefifteensubjectsinterredinthepupastage，fourteeneasilyreachthesurfacewhentheybecomeflies。Onlyoneofthemperishes，onewhohasnotevenattemptedtheascent。Withtwelvecentimetersofsand，fouremerge。Withtwentycentimeters，two，nomore。Theotherflies，jadedwiththeirexertions，havediedatahigherorlowerstageoftheroad。Lastly，withyetanothertubewhereinthecolumnofsandmeasuredsixtycentimeters，Iobtainedtheliberationofonlyasinglefly。Thepluckycreaturemusthavehadahardstruggletomountfromsogreatadepth，fortheotherfourteendidnotevenmanagetoburstthelidoftheircaskets。
Ipresumethattheloosenessofthesandandtheconsequentpressureineverydirection，similartothatexercisedbyfluids，haveacertainbearingonthedifficultiesoftheexhumation。Twomoretubesareprepared，butthistimesuppliedwithfreshmould，lightlyheapedup，whichhasnottheincoherenceofsand，withtheattendantdrawbackofpressure。Sixcentimetersofmouldgivemeeightfliesforfifteenpupaeburied;twentycentimetersgivemeonlyone。Thereislesssuccessthanwiththesandycolumn。Mydevicehasdiminishedthepressure，but，atthesametime，increasedthepassiveresistance。Thesandfallsofitselfundertheimpactofthefrontalrammer;theunyieldingmoulddemandsthecuttingofagallery。Infact，Iperceive，ontheroadfollowed，ashaftwhichcontinuesindefinitelysuchasitis。Theflyhasboreditwiththetemporaryblisterthatthrobsbetweenhereyes。
Ineverymedium，therefore，whethersand，mouldoranyearthycombination，greatarethesufferingsthatattendtheexhumationofthefly。Andsothemaggotshunsthedepthswhichadesireforadditionalsecuritymightseemtorecommend。Thewormhasitsownprudence:foreseeingthedangersahead，itrefrainsfrommakinggreatdescentsthatmightpromotethewelfareofthemoment。Itneglectsthepresentforthesakeofthefuture。
CHAPTERXVIAPARASITEOFTHEMAGGOT
Thedangersoftheexhumationarenottheonlyones;theBluebottlemustbeacquaintedwithothers。Life，whenallissaid，isaknacker’syardwhereinthedevoureroftodaybecomesthedevouredoftomorrow;andtherobberofthedeadcannotfailtoberobbedofherownlifewhenthetimecomes。IknowthatshehasoneexterminatorinthepersonofthetinySaprinusbeetle，afisheroffatsausagesontheedgeofthepoolsformedbyliquescentcorpses。
Hereswarmincommonthegrubsofthegreenbottle，thefleshflyandthebluebottle。TheSaprinusdrawsthemtohimfromthebankandgobblesthemindiscriminately。Theyrepresenttohimmorselsofequalvalue。
Thisbanquetcanbeobservedonlyintheopencountry，undertheraysofahotsun。Sapriniandgreenbottlesneverenterourhouses;thefleshflyvisitsusbutdiscreetly，doesnotfeelathomewithus;theonlyonewhocomesfussingalongisthebluebottle，whothusescapesthetributeduetotheconsumerofplumpsausages。But，inthefields，whereshereadilylayshereggsuponanycarcassthatshefinds，she，aswellastheothers，seesherverminsweptawaybythegluttonousSaprinus。
Inaddition，graverdisastersdecimateherfamily，if，asIdonotdoubt，wecanapplytothebluebottlewhatIhaveseenhappeninthecaseofherrival，thefleshfly。Sofar，IhavehadnoopportunityofactuallyperceivingwiththefirstwhatIhavetotellofthesecond;still，Idonothesitatetorepeatabouttheonewhatobservationhastaughtmeabouttheother，forthelarvalanalogiesbetweenthetwofliesareveryclose。
Herearethefacts。Ihavegatheredanumberofpupaeofthefleshflyinoneofmyverminjars。Wishingtoexaminethepupa’shinderend，whichishollowedintoacupandscallopedintoacoronet，I
staveinoneofthelittlebarrelsandforceopenthelastsegmentswiththepointofmypocketknife。ThehornykegdoesnotcontainwhatIexpectedtofind:itisfulloftinygrubspackedoneatoptheotherwiththesameeconomyofspaceasanchoviesinabottle。
Savefortheskin，whichhashardenedintoabrownshell，thesubstanceofthemaggothasdisappeared，changedintoarestlessswarm。
Therearethirty—fiveoccupants。Ireplacethemintheircasket。
Therestofmyharvest，wherein，nodoubt，areotherpupaesimilarlystocked，isarrangedintubesthatwilleasilyshowmewhathappens。Thethingtodiscoveriswhatgenusofparasitesthegrubsenclosedbelongto。Butitisnotdifficult，withoutwaitingforthehatchingoftheadults，torecognizetheirnaturemerelybytheirmodeoflife。TheyformpartofthefamilyofChalcididae，whoaremicroscopicravagersoflivingentrails。
Notlongago，inwinter，Itookfromthechrysalisofagreatpeacockmothfourhundredandforty—nineparasitesbelongingtothesamegroup。Thewholesubstanceofthefuturemothhaddisappeared，allbutthenymphalwrapper，whichwasintactandformedahandsomeRussia—leatherwallet。Thewormgrubswerehereheapedupandsqueezedtogethertothepointofstickingtooneanother。Thehairpencilextractstheminbundlesandcannotseparatethemwithoutsomedifficulty。Theholdingcapacityisstrainedtotheutmost;thesubstanceofthevanishedMothwouldnotfillitbetter。Thatwhichdiedhasbeenreplacedbyalivingmassofequaldimensions，butsubdivided。Thepriceofthiscolony’sexistenceistheconversionofthechrysalisintoasortofmilkfoodofdoubtfulconstitution。Theenormousudderhasbeendrainedoutright。
Youshudderwhenyouthinkofthatbuddingfleshnibbledbitbybitbyfourorfivehundredgormandizers;thehorrifiedimaginationrefusestopicturetheanguishsufferedbythetorturedwretch。
Butistherereallyanypain？Wehaveleavetodoubtit。Painisapatentofnobility;itismorepronouncedinproportionasthesuffererbelongstoahigherorder。Inthelowerranksofanimallife，itmustbegreatlyreduced，perhapsevennil，especiallywhenlife，inthethroesofevolution，hasnotyetacquiredastableequilibrium。Thewhiteofaneggislivingmatter，butendurestheprickofaneedlewithoutaquiver。Woulditnotbethesamewiththechrysalisofthegreatpeacock，dissectedcellbycellbyhundredsofinfinitesimalanatomists？Woulditnotbethesamewiththepupaofthefleshfly？Theseareorganismsputbackintothecrucible，revertingtotheeggstateforasecondbirth。Thereisreasontobelieve，therefore，thattheirdestructioncrumbbycrumbismerciful。
TowardstheendofAugust，theparasiteofthefleshfly’sgrubsmakesherappearanceoutofdoorsintheadultform。SheisaChalcidid，asIexpected。Sheissuesfromthebarrelthroughoneortwolittleroundholeswhichtheprisonershavepiercedwithapatienttooth。Icountsomethirtytoeachpupa。Therewouldnotbeenoughroomintheabodeifthefamilywerelarger。
Theimpisaslimandelegantcreature，butoh，howsmall！Shemeasureshardlytwomillimeters。Hergarbisbronzedblack，withpalelegsandaheartshaped，pointed，slightlypedunculateabdomen，withneveratraceofaprobeforinoculatingtheeggs。
Theheadistransversal，thewidthexceedingthelength。
Themaleisonlyhalfthesizeofthefemale;heisalsoverymuchlessnumerous。Perhapspairingishere，asweseeelsewhere，asecondarymatterfromwhichitispossibletoabstain，inpart，withoutinjuringtheprospectsoftherace。Nevertheless，inthetubewhereinIhavehousedtheswarm，thefewmaleslostamongthecrowdardentlywoothepassingfair。Thereismuchtobedoneoutside，aslongasthefleshfly’sseasonlasts;thingsareurgent;andeachpigmyhurriesasfastasshecantotakeupherpartasanexterminator。
Howistheparasite’sinroadintothefleshfly’spupaeeffected？
Truthisalwaysveiledinacertainmystery。Thegoodfortunethatsecuredmetheravagedpupataughtmenothingconcerningthetacticsoftheravager。IhaveneverseentheChalcididexplorethecontentsofmyappliances;myattentionwasengagedelsewhereandnothingissodifficulttoseeasathingnotyetsuspected。
But，thoughdirectobservationbelacking，logicwilltellusapproximatelywhatwewanttoknow。
Itisevident，tobeginwith，thattheinvasioncannothavebeenmadethroughthesturdyamourofthepupae。Thisistoohardtobepenetratedbythemeansatthepigmy’sdisposal。Naughtbutthedelicateskinofthemaggotslendsitselftotheintroductionofthegerms。Anegglayingmother，therefore，appears，inspectsthesurfaceofthepoolofsaniesswarmingwithgrubs，selectstheonethatsuitsherandperchesonit;then，withthetipofherpointedabdomen，whenceemerges，foraninstant，ashortprobekepthiddenuntilthen，sheoperatesonthepatient，perforatinghispaunchwithadexterouswoundintowhichthegermsareinserted。
Probably，anumberofpricksareadministered，asthepresenceofthirtyparasitesseemstodemand。
Anyway，themaggot’sskinispiercedateitheronepointormany;
andthishappenswhilethegrubisswimminginthepoolsformedbytheputridflesh。Havingsaidthis，wearefacedwithaquestionofseriousinterest。Tosetitforthnecessitatesadigressionwhichseemstohavenothingtodowiththesubjectinhandandisneverthelessconnectedwithitintheclosestfashion。Withoutcertainpreliminaries，theremainderwouldbeunintelligible。Sonowforthepreliminaries。
IwasinthosedaysbusywiththepoisonoftheLanguedocianscorpionanditsactionuponinsects。Todirectthestingtowardthisortheotherpartofthevictimandmoreovertoregulateitsemissionwouldbeabsolutelyimpossibleandalsoverydangerous，aslongasthescorpionswereallowedtoactastheypleased。I
wishedtobeablemyselftochoosetheparttobewounded;I
likewisewishedtovarythedoseofpoisonatwill。Howtosetaboutit？Thescorpionhasnojarlikereceptacleinwhichthevenomisaccumulatedandstored，likethatpossessed，forinstance，bythewaspandthebee。Thelastsegmentofthetail，gourdshapedandsurmountedbythesting，containsonlyapowerfulmassofmusclesalongwhichliethedelicatevesselsthatsecretethepoison。