Famennian crinoids from northwest China
A Platycrinoid with recumbent arms
This picture is a side view of Chinacrinus, an unusual platycrinoid
with permanently recumbent arms that completely enclosed the calyx in life.
This specimen shows that the arms were impressed against the calyx so that
scars were left on the plates that exhibit the biserial nature of the arms.
The arms fell off the dead crinoid before it was buried, thus exposing
the scarred calyx plates.
Chinacrinus was described by Lane et al., 1997, Paleontological
Society, vol 71, supplment to no. 2.
