My dear Sir

Many thanks about M^r Zurhorst; I will not write.²

With respect to the duck I have considered the case well & am convinced that all the breeds including the Black Labrador & Penguin are the descendants of the common Wild Duck.³ With respect to the goose there is more difficulty from the existence of 3 or 4 closely allied European wild species, & there is no indirect evidence as in the case of the duck. The evidence as far as it goes supports the belief of many good naturalists that the domestic bird is descended from the wild Grey Lag Goose, anser ferus.⁴

I have not attended to the guinea fowl & did not know that there was any doubt about its origin; I saw plenty of the wild bird in the Cape de Verd islands.⁵

I hope this is the kind of information which you require

My dear Sir | Yours very faithfully | Ch. Darwin