Columbia subject headings:
Paleontology--England.
Paleontology--Great Britain.
Paleontology--Jurassic.
Sea urchins, Fossil--England.
Sea urchins, Fossil--Great Britain.
Harvard subject headings:
Paleontology--England.
Paleontology--Great Britain
Paleontology--Jurassic
Sea urchins, Fossil--England.
Sea urchins, Fossil--Great Britain.
Princeton subject headings:
Paleontology--England.
Paleontology--Great Britain.
Paleontology--Jurassic.
Sea urchins, Fossil--England.
Sea urchins, Fossil--Great Britain.