Note:  Do not rely on this information. It is very old.

Pentacrinus

Pentacrinus, the type-genus of the Pentacrinidce, one of the best-known families of Sealilies. It was most abundant in Mesozoic times, and tie joints of its stems are very common in some Oolitic and Liassic beds. The stems were in some cases 80 feet in height.