Published in Annals of the Missouri Botanical Garden, in 1931, in volume 18, pages 1-8

Published in Annals of the Missouri Botanical Garden, in 1931, in volume 18, pages 41-55

Published in Annals of the Missouri Botanical Garden, in 1931, in volume 18, pages 57-95

Published in Annals of the Missouri Botanical Garden, in 1931, in volume 18, pages 9-16

Published in Annals of the Missouri Botanical Garden, in 1931, in volume 18, pages 17-40

Published in Annals of the Missouri Botanical Garden, in 1931, in volume 18, pages 245-282

Published in Annals of the Missouri Botanical Garden, in 1931, in volume 18, pages 287-456

Published in Annals of the Missouri Botanical Garden, in 1931, in volume 18, pages 457-464

Published in Annals of the Missouri Botanical Garden, in 1931, in volume 18, pages 489-508

Published in Annals of the Missouri Botanical Garden, in 1931, in volume 18, pages 509-540

Published in Annals of the Missouri Botanical Garden, in 1931, in volume 18, pages 541-556

Published in Annals of the Missouri Botanical Garden, in 1931, in volume 18, pages 565-572

Published in Annals of the Missouri Botanical Garden, in 1931, in volume 18, pages 117-244

Published in Annals of the Missouri Botanical Garden, in 1931, in volume 18, pages 97-116

Published in Annals of the Missouri Botanical Garden, in 1931, in volume 18, pages 469-487

Published in Annals of the Missouri Botanical Garden, in 1931, in volume 18, pages 465-468

Published in Annals of the Missouri Botanical Garden, in 1931, in volume 18, pages 557-563