GENERAL HISTOLOGY

Detailed explanation-1: -Woodocrinus was a type of animal known as a crinoid, or sea lily. Although they look like plants, crinoids are close relatives of sea urchins and starfish. Woodocrinus grew in large groups in the shallow seas near modern-day Europe.

Detailed explanation-2: -Crinoids that are attached to the sea bottom by a stalk in their adult form are commonly called sea lilies, while the unstalked forms are called feather stars or comatulids, which are members of the largest crinoid order, Comatulida.

Detailed explanation-3: -Crinoids are known as sea lilies because they live on a stem and have a flower-like body. They are analogous to starfish with a stem. Although still existing but uncommon in the oceans today, they were very abundant in shallow tropical seas during the Paleozoic.

Detailed explanation-4: -Like their relatives-starfishes, sea urchins, sea cucumbers, and brittle stars-crinoids are echinoderms, animals with rough, spiny surfaces and a special kind of radial symmetry based on five or multiples of five.

Detailed explanation-5: -Sea lilies have a stalk below the crown and look like flowers. Feather stars have a cluster of tentacles below the crown and look like ferns. The arms of both animals usually have branches, as many as two hundred in some species. Each arm and branch has a food groove lined with grabbers called tube feet.