M。Prevostalone，Ithink，hasthrownlightbyhisobservations[9]onthispuzzle：hefindsthatthefemalecuckoo，which，accordingtomostobservers，laysatleastfromfourtosixeggs，mustpairwiththemaleeachtimeafterlayingonlyoneortwoeggs。Now，ifthecuckoowasobligedtositonherowneggs，shewouldeitherhavetositonalltogether，andthereforeleavethosefirstlaidsolong，thattheyprobablywouldbecomeaddled；orshewouldhavetohatchseparatelyeachegg，ortwoeggs，assoonaslaid：butasthecuckoostaysashortertimeinthiscountrythananyothermigratorybird，shecertainlywouldnothavetimeenoughforthesuccessivehatchings。Hencewecanperceiveinthefactofthecuckoopairingseveraltimes，andlayinghereggsatintervals，thecauseofherdepositinghereggsinotherbirds’nests，andleavingthemtothecareoffoster-parents。Iamstronglyinclinedtobelievethatthisviewiscorrect，fromhavingbeenindependentlyledasweshallhereaftersee

　　toananalogousconclusionwithregardtotheSouthAmericanostrich，thefemalesofwhichareparasitical，ifImaysoexpressit，oneachother；

　　eachfemalelayingseveraleggsinthenestsofseveralotherfemales，andthemaleostrichundertakingallthecaresofincubation，likethestrangefoster-parentswiththecuckoo。

　　Iwillmentiononlytwootherbirds，whichareverycommon，andrenderthemselvesprominentfromtheirhabits。TheSaurophagussulphuratusistypicalofthegreatAmericantribeoftyrant-flycatchers。Initsstructureitcloselyapproachesthetrueshrikes，butinitshabitsmaybecomparedtomanybirds。Ihavefrequentlyobservedit，huntingafield，hoveringoveronespotlikeahawk，andthenproceedingontoanother。Whenseenthussuspendedintheair，itmightveryreadilyatashortdistancebemistakenforoneoftheRapaciousorder；itsstoop，however，isveryinferiorinforceandrapiditytothatofahawk。AtothertimestheSaurophagushauntstheneighbourhoodofwater，andthere，likeakingfisher，remainingstationary，itcatchesanysmallfishwhichmaycomenearthemargin。Thesebirdsarenotunfrequentlykepteitherincagesorincourtyards，withtheirwingscut。Theysoonbecometame，andareveryamusingfromtheircunningoddmanners，whichweredescribedtomeasbeingsimilartothoseofthecommonmagpie。Theirflightisundulatory，fortheweightoftheheadandbillappearstoogreatforthebody。IntheeveningtheSaurophagustakesitsstandonabush，oftenbytheroadside，andcontinuallyrepeatswithoutachangeashrillandratheragreeablecry，whichsomewhatresemblesarticulatewords：theSpaniardssayitislikethewords“Bienteveo“

　　Iseeyouwell，andaccordinglyhavegivenitthisname。

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