Graptolite
From Wikipedia, the free encyclopedia.

Graptolites (Graptolita) are colonial animals known from the Upper Cambrian through the Mississippian. Possibly hemichordates. A possible graptolite, Chaunograptus, is known from the Middle Cambrian.

Any information on graptolite exhibitions at natural history museums?

The original article can be found at: http://en.wikipedia.org/wiki/Graptolite.
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