From:
http://en.wikipedia.org/wiki/Sheep%E2%80%93goat_hybridquoting: "Darwinism – An Exposition Of The Theory Of Natural Selection With Some Of Its Applications (1889)"
"It has been long known to shepherds, though questioned by naturalists, that the progeny of the cross between the sheep and goat is fertile. Breeds of this mixed race are numerous in the north of Europe.""