Helmet shell definitions

Helmet-shell

{rdt intro|Paoli/Thorndale Line of SEPTA} Category:Templates for SEPTA lines ...
Found on http://en.wikipedia.org/wiki/Helmet-shell

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helmet shell

any marine snail of the family Cassidae (subclass Prosobranchia, class Gastropoda), characterized by a large, thick shell with a shieldlike inner ... [1 related articles]
Found on http://www.britannica.com/eb/a-z/h/34

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Helmet-Shell

Helmet-shell is a common name for molluscs of the genus Cassis, gastropods of the family Buccinidae found mainly on tropical shores.
Found on http://www.probertencyclopaedia.com/browse/BH.HTM

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