North American flora - New York Botanical Garden (New York Botanical Garden, 1907)

North American flora - New York Botanical Garden (New York Botanical Garden, 1914)

North American flora - New York Botanical Garden (New York Botanical Garden, 1917)

North American flora - New York Botanical Garden (New York Botanical Garden, 1924)

North American flora - New York Botanical Garden (New York Botanical Garden, 1932)