The preparation of the last map (Pl. IV), showing the present distribution of European races, was in some respects a more intricate task than that of the earlier maps. The main difficulty is that, as a result of successive migrations and expansions, the different races of Europe are now often represented by distinct classes. Numerically one type may be in a majority, as are the Rumanians in eastern Hungary, where they constitute nearly two-thirds of the population. At the same time this majority is of no intellectual or social importance, since all the professional and military classes in Transylvania are either Magyar or Saxon. Under the existing scheme of showing majorities by color these ruling minorities do not appear at all. In this last map the yellow is beginning to expand, especially in the British Isles. The green also is recovering somewhat in central and western Europe, but in the Balkans, eastern Germany, Austria and above all in Poland and Russia, it has largely replaced the former Nordic color. The pink, _i. e._, the continental Nordics as a distinct type, has entirely vanished and has been everywhere replaced by the Teutonic red. This does not mean that there are no existing remnants of the continental Nordics, but it does mean that these remnants cannot now be distinguished from the all-pervading and masterful type of the Teutonic Nordics. In general, this last map, as compared with the earlier ones, although showing a steady shrinkage of the Nordic area, brings out clearly the manner in which it centres around the basins of the Baltic and the North Sea, radiating thence in every direction and in decreasing numbers. The menace of the continued expansion of the green area westward and northward into the red area of the Nordics is undoubtedly one of the causes of the present world war. This expansion began as far back as the fall of Rome, but only in our day and generation has this backward race even claimed a parity of strength and culture with the Master Race. DOCUMENTARY SUPPLEMENT The purpose of these notes is to meet an insistent demand for authorities for the statements made in the body of the book. As was mentioned in the Introduction, in a work of this compass and aim, mere lack of space forbade all but the barest outlines, so that often an appearance of dogmatism was the result. There is a vast literature on the subjects discussed and to give all the references would be almost a physical impossibility. It is particularly difficult to name all that has appeared in periodicals, since they have become so numerous, especially during the last few years.