CHAPTER1。XIII。
THEWRITINGOFTHE’ORIGINOFSPECIES。’
JUNE18，1858，TONOVEMBER，1859。
[Thelettersgiveninthepresentchaptertelltheirstorywithsufficientclearness，andneedbutafewwordsofexplanation。Mr。Wallace’sEssay，referredtointhefirstletter，borethesub—title，’OntheTendencyofVarietiestodepartindefinitelyfromtheOriginalType，’waspublishedintheLinneanSociety’sJournal（1858，volumeiii。page53）aspartofthejointpaperof\"Messrs。C。DarwinandA。Wallace，\"ofwhichthefulltitlewas’OntheTendencyofSpeciestoformVarieties;andonthePerpetuationofVarietiesandSpeciesbyNaturalMeansofSelection。’
Myfather’scontributiontothepaperconsistedof（1）Extractsfromthesketchof1844;（2）partofaletteraddressedtoDrAsaGray，datedSeptember5，1857，andwhichisgivenabove。Thepaperwas\"communicated\"