Columbia subject headings:
Darwin, Charles, 1809-1882--Correspondence--Catalogs.
Naturalists--England--Correspondence--Catalogs.
Harvard subject headings:
Darwin, Charles, 1809-1882
Darwin, Charles, 1809-1882--Catalogs.
Naturalists--England--Correspondence.
Naturalists--Great Britain--Correspondence--Catalogs.
Princeton subject headings:
Darwin, Charles, 1809-1882--Correspondence--Catalogs.
Naturalists--England--Correspondence--Catalogs.