Wonderful fossils Cystoids

Description

Excellent  four specimen Sea bladders or cystoids (Cystoidea) are an extinct class of the type of echinoderms (Echinodermata). They existed in the first half of the Paleozoic - they arose in the Ordovician and became extinct in the Devonian. According to some reports, some species survived to the Permian. They are considered the closest, albeit more primitive, relatives of sea lilies - the crinoids.
These specimen are from the Ordovician of Russia
The specimen is sent to any country...