Columbia subject headings:
Botany.
Geology.
Natural history.
Zoology.
Harvard subject headings:
Botany--Periodicals
Geology--Periodicals
Natural history--Periodicals
Zoology--Periodicals
Princeton subject headings:
Botany--Periodicals.
Geology--Periodicals.
Natural history--Periodicals.
Periodicals.
Zoology--Periodicals.