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