3 vols, 1925-1962. Vol. 1 (Polypetalae), in 4 parts: 1: [I]-198, 5 Mar 1925 2: 199-358, 10 Oct 1926 3: 359-562, 20 Sep 1928 4: 563-809, 28 Mar 1931. Vol. 2 (Caprifoliaceae to Apocynaceae), in 5 parts: 1: 1-146, 12 Mar 1932 2: [i-ii] 147-234, 28 Feb 1934 3: 235-310, Jan 1936 4: 311-393, May 1938 5: 395-476, Jan 1939. Vol. 3 (Asclepiadaceae to Gesneriaceae), in 3 parts: pt. 1, Aug 1951 pt. 2, Jan 1954 pt. 3, Nov 1962.