The doctrine of the origin of our several domestic races from several aboriginal stocks, has been carried to an absurd extreme by some authors.

They believe that every race which breeds true, let the distinctive characters be ever so slight, has had its wild prototype.

At this rate there must have existed at least a score of species of wild cattle, as many sheep, and several goats, in Europe alone, and several even within Great Britain.

One author believes that there formerly existed eleven wild species of sheep peculiar to Great Britain! When we bear in mind that Britain has now not one peculiar mammal, and France but few distinct from those of Germany, and so with Hungary, Spain, etc.