All this suggests numerous questions—but they are questions of minute rather than general ethnology. The latter takes us to the consideration of the populations of the frontier. Here we find—

Of these, the last are recent intruders; so that the real ethnology to be considered is that of ancient Thrace. Unfortunately this is as obscure as that of Asia Minor itself.

The Greeks of the Ægean are probably intrusive; the other three are ancient occupants of their present areas.

Now, in arguing upon the conditions afforded by this frontier, it is legitimate to suppose that each of the populations belonging to it had some extension beyond their present limits, in which case the à-priori probabilities would be that—

Now, the population of Asia Minor may have been a mere extension of the populations of the frontiers—one or all.

But it also may have been separate and distinct from any of them.