On The Origin of Species by Charles Darwin Chapter 13 Page 14

fresh-water birds, which have great powers of flight, and naturally travel from one piece of water to another.

2. On The Inhabitants Of Oceanic Islands

We now come to the last of the three classes of facts, which I have selected as presenting the greatest amount of difficulty with respect to distribution, on the view that not only all the individuals of the same species have migrated from some one area, but that allied species, although now inhabiting the most distant points, have proceeded from a single area, the birthplace of their early progenitors.

I have already given my reasons for disbelieving in continental extensions within the period of existing species on so enormous a scale that all the many islands of the several oceans were thus stocked