General Accounts.--Historical significance of geography of the United States: H. Mill, _International Geography_, ch. xxxix.; F. Ratzel, _Vereinigte Staaten_, I. ch. ii.; B. Hinsdale, _How to Study and Teach History_, ch. xiv.; E. Bogart, _Economic History of United States_, introduction; E. Semple, _American History and its Geographic Conditions_; A. Brigham, _Geographic Influences in American History_; W. Scaife, _America: its Geographical History_.--Topographical descriptions of the country: J. Whitney, _United States_, I. pt. i.; N. Shaler, _United States_, I., and _Nature and Man in America_; Mill, as above; E. Reclus, _North America_, III.; Hinsdale, as above, ch. xv.--Prehistoric Man in America: L. Morgan, _Ancient Society_; J. Nadaillac, _Prehistoric America_; J. Foster, _Prehistoric Races_; Winsor, as above, I. ch. vi.; E. Avery, _United States and its People_, I. chs. i., ii.; Farrand, as above, ch. v.--The Indians (or Amerinds): D. Brinton, _American Race_; C. Thomas, _Indians in Historic Times_; F. Hodge, _Handbook of American Indians_; Farrand, as above, chs. vi.-xviii.; Avery, as above, I. ch. xxii.; F. Dellenbaugh, _North Americans of Yesterday_; S. Drake, _Aboriginal Races of America_; G. Ellis, _Red Man and White Man in North America_; G. Grinnell, _Story of the Indian_. The introduction to F. Parkman, _Jesuits in North America_, and his _Conspiracy of Pontiac_, I. ch. i., are admirable general surveys. Briefer, also excellent, is J. Fiske's _Discovery of America_, I. ch. i. The mound-builders have now been identified as Indians. L. Carr, _Mounds of the Mississippi Valley Historically Considered_ is the best exposition of this subject. C. Thomas, _Catalogue of Prehistoric Works East of the Rocky Mountains_ is useful. Special Histories.--Larned, _History for Ready Reference_, I. 83-115, gives brief account and bibliographies of tribes; Farrand, as above, 279-286, does the same by geographical groups. Especially notable are L. Morgan, _League of the Iroquois_, and C. Colden, _Five Indian Nations_. For detailed treatment of the aborigines of that section, consult H. Bancroft, _Native Races of the Pacific Coast_, II., and _Mexico_, I.; J. Palfrey, _New England_, I. chs. i., ii., describes the Indians in that region; T. Roosevelt, _Winning of the West_, I. chs. iii., iv., the Southern tribes; and Parkman, _Pontiac_, the old Northwest tribes. There are numerous biographies of chiefs, and a considerable literature on border warfare. 2. Physical Characteristics of North America. Sidenote: Origin of the native races, a mere matter of conjecture.