Fossils index

Crinoids

Crinoids live in the sea. Their name is derived from krinoeides (Greek) which means 'like a lily'. They are also called sea lilies or feather-stars.

Kingdom: Animalia
Phylum: Echinodermata
Subphylum: Crinozoa
Class: Crinoidea
Crinoid arms Crinoids are animals despite their name. They are related to starfish and echinoids. These often have 5 fold symmetry. The photo on the left shows the inside of a crenoid stem. You can see the hole is a a five pointed star.

The crinoid is the state fossil of Missouri, USA.

Crinoid stem - side

Timescale: Crinoids have been around for a long time, about 480 million years ago. There are still crinoids alive today.

Crinoid arms A crinoid has three parts, a stem which it uses to stick to the sea floor, a calyx or body, and its arms which it uses to catch its food. Usually it's the stem which is found as a fossil, but on the left you can see some fossil crinoid arms. On the right are some living crinoids. A living crinoid A living crinoid
Crinoid stem - side Crinoid stem - end This is part of the stem of a crinoid, from the side and from the top. They used to be called St Cuthbert's Beads. St Cuthbert lived at Lindisfarne, and was supposed to use the fossils as rosary beads. In Derbyshire, they are called screwstones, as the shape looks like a screw. However, the grooves don't make a spiral like a proper screw. Some crinoid stems have the shape of a star, and they are called star stones. They were thought to have been made in the clouds and dropped during thunder-storms. In Malta, these stones were supposed to have been blessed by St Paul, who stayed on the island, and they protected you against poison. Size of fossil: 15mm


These crinoid stems were found on Castleton beach, in the Isle of Man. You can see that two of pictures show the sections, called columnals, have separated and just look like discs. In Germany, these are called Bonifacius Pfennige or St Boniface's pennies.
Sizes: 6mm-27mm
Crinoid stems Crinoid stems
Crinoid stems Crinoid stems


Crinoids are rare nowadays but in the past they were common, so there are a lot of crinoid fossils. Here is a type of rock called crinoid limestone, which is mostly crinoids! It comes from near Edinburgh, Scotland. It is Carboniferous, about 300 million years old. The two photos show both sides of the rock. See if you can find the crinoid with a star-shaped hole. Size of stone: 85mm

Crinoid limestone
Crinoid limestone



This is another piece of massed crinoids. It has been polished to show the structure better. This shows top and bottom. Size: 22mm

Crinoids Crinoids



This is a rock with crinoid stems on one side, and crinoid arms on the other. Size: 78mm Crinoid stems Crinoid arms