Columbia subject headings:
Harvard subject headings:
Botanists--Great Britain--Biography--Congresses.
Botany--Amazon River Region--Congresses.
Botany--Great Britain--Congresses.
Plant collecting--Amazon River Region--History--Congresses.
Scientific expeditions--Amazon River Region--History--Congresses.
Spruce, Richard, 1817-1893--Congresses.
Princeton subject headings:
Spruce, Richard, 1817-1893--Bibliography.
Spruce, Richard, 1817-1893--Congresses.