With Selected Poems, 1963, Ransom's canon of “authorized” poems stands at fifty-three. Comparison of this latest collection with his 1945 and 1955 collections reveals minor and major changes of the 1945 and 1955 collections, particularly in his lesser-known poems, and inclusion of revised versions of earlier poems. Most changes show Ransom simplifying diction, smoothing meter, or removing obscurities. Minor changes (word and punctuation changes) occur in eight poems. Major changes (revisions of whole lines, addition or deletion of material longer than one line, and complete revision) occur in fourteen poems (“Agitato ma non troppo,” “First Travels of Max,” “Armageddon,” “Prometheus in Straits,” “Eclogue,” “Hilda,” “What Ducks Require,” “Master's in the Garden Again,” and others). “Old Man Pondered,” reprinted without change from the Saturday Review of Literature, is considered a major change since it did not appear in the 1945 or 1955 collections.