archaic forms of language and culture, as among the
Lithuanians of Aryan speech among the Baltic swamps, it may indicate
that the locality formed a segregated corner of the early center of
dispersion. It seems essential to such an original seat that, whether
large or small, it should be marked by some degree of isolation, as the
condition for the development of specific racial characteristics.

The complexity of this question of ethnic origins is typical of
anthropo-geographic problems, typical also in the warning which it gives
against any rigidly systematic method of solution. The whole science of
anthropo-geography is as yet too young for hard-and-fast rules, and its
subject matter too complex for formulas.

NOTES TO CHAPTER IV

[126] H.J. Mackinder, Britain and the British Seas, pp. 179-187. London,
1904. W.Z. Ripley, The Races of Europe, pp. 306-310, 319-326. New York,
1899.

[127] Compare observations of Georg Schweinfurth, The Heart of Africa,
Vol. I, pp. 312-313. London, 1873.

[128] Nott and Gliddon, Types of Mankind, p. lvii. Philadelphia, 1868.

[129] D.M. Wallace, Russia, pp. 151-155. New York, 1904.

[130] Thucydides, Book I, chap. II.

[131] Strabo, Book II, chap. III, 7.

[132] McGee and Thomas, Prehistoric North America, pp. 408-414, Vol. XIX
of _History of North America_, edited by T.N. Thorpe. Philadelphia,
1905.

[133] Hodgkin, Italy and Her Invaders, Vol. II, p. 214. Oxford, 1892.

[134] Sir John Lubbock, Prehistoric Times, p. 587. New York, 1872.

[135] D.G. Brinton, The American Race, pp. 116-119. Philadelphia, 1901.

[136] O.T. Mason, Primitive Travel and Transportation, pp. 249-250.
_Smithsonian Report_, Washington, 1896.

[137] Thucydides, Book I, chap. II.

[138] Edward A. Boss, Foundations of Sociology, pp. 359-363, 386-389.
New York, 1905.

[139] D.G. Brinton, Races and Peoples, pp. 73-75. Philadelphia, 1901.

[140] John Richard Green, The Making of England, Vol. I, pp. 9-11,
45-46, 52-54, 57, 62. London, 1904.

[141] James Bryce, The Migration of the Races of Men Considered
Historically, _Scottish Geographical Magazine_, Vol. VIII, pp. 400-421,
and _Smithsonian Report_ for 1893, pp. 567-588.

[142] Caesar, _De Bello Gallico_, Book II, chap. 29.

[143] Motley, Rise of the Dutch Republic, Vol. I, p. 5. New York, 1883.

[144] John Richard Green, The Making of England, Vol. I, p. 46. London,
1904.

[145] Hodgkin, Italy and Her Invaders, Vol. V, pp. 99-101. Oxford,
1