Osborn, Henry Fairfield, 1857-1935.2020-05-112020-05-111926http://digitallibrary.amnh.org/handle/2246/719746 p. : ill. (1 col.), map ; 25 cm.Reprinted from Natural history, vol. XXIII, 1923, no. 1, pp. 3-24 and vol. XXV, 1925, no. 1, pp. 3-23.en-USMastodons -- North America.Mammoths -- North America.Mammals, Fossil -- North America.Other