Correspondence, 1923-1932 and n.d. TLS's, typescript carbons, and holographs. 43 letters including a few postcards. The letters concern primarily Ostrander's research and writing and the sale of his publications. Many cover notes in the collection show that he was in the habit of sending both originals and copies of his correspondence to RSE for the latter's collection. All letters that directly addressed RSE were filed in the correspondence file. Those that would have constituted a slice of the Ostrander correspondence with people other than RSE are filed here. Ostrander's correspondents included the following: Bisbee, Gen. Wm. H.; Brininstool, Earl ("Pard"); Bruce, Robert; Carter, R. G.; Hall, Henry; Hebard, Grace Raymond; Jackson, Wm. H.; Joseph Chief White Bull; Lemmon, G. E.; and Lockard, F. M.