range of Australian genera of, 485
Struthious birds, probable origin of, 287
Stylinodontidæ, N. American Eocene, 139
Stylinodontia, N. American Eocene, 139
Sub-regions, on what principle formed, 80
Palæarctic, 191
Ethiopian, 258
Oriental, 321
Australian, 408
Suidæ, European Miocene, 119