Crinoid “Feather Stars” Columnal Segments Fashion

Description

Crinoid “Feather Stars” Columnal Segments

Above: Front of Specimen Card

Sometimes referred to as feather stars or sea lilies, Crinoids are members of an extended and very ancient family of sea animals known as echinoderms. Echinoderms date back as far as the Cambrian period some 541,000,000 years ago. They include such varied animals as sea urchins, sea cucumbers, and starfish. Their development was part of a much larger explosion of complex life on Earth which resulted in most of the animal or metazoan body plans we know today.

Above: A selection of Crinoid columnal segments.

Originally part of the Third Edition collection, this specimen is a hand-selected assortment of crinoid stem segments, also known as “columnals”. They were recovered near Talsint, Morocco. The fossil beds in this region are from the Bajocian Age of the Middle Jurassic Period and date to roughly 170,000,000 years old.

The specimen comes inside an acrylic specimen jar, encased in a classic, glass-topped riker display case measuring 4 1/2″ x 3 1/2″. A small information card is also enclosed that also serves as the certificate of authenticity.

Please Note: Each specimen will be unique with varying degrees of detail. Pictures included on this page are representative one. Each jar should have 5-7 segments depending on their size.

More about Crinoids and Fossil History

Breaking down body plans into their simplest form involves looking at a concept known as symmetry. Symmetry in biology means that bodies can be divided in various ways which are more or less identical to each other.

Above: A modern-day Crinoid

There are three very basic forms of symmetry in biology: bi-lateral, spherical, and radial. Humans exhibit bilateral symmetry, with our bodies organized along a centerline. Spherical symmetry is generally limited to very small organisms like algae which form spherical colonies. The last form, called radial symmetry, is a bit like a pie where body parts are arranged around a central axis.

There are a number of variants to this radial symmetry wherein body parts are separated into four, five, six, or even eight symmetrical pieces. Echinoderms are the only animals that exhibit the five-part, or pentaradial form of radial symmetry. This body plan also happens to result in interesting fossil shapes.

Above: Crinoid drawings by Ernst Haeckel from “Kunstformen der Natur” (Art Forms of Nature, 1904)

Before they were identified as fossils, segmented Crinoid stems were sometimes referred to as “fairy money”. This is not so different from the way other fossils were viewed, such as “snake stones” (fossil ammonites) or “snake tongues” (fossil shark teeth).

Crinoid stems also worked their way in Christian legends in both Germany and England where they were known as St. Boniface’s pfennige (pennies) and St. Cuthbert’s beads. The latter is particularly interesting in the context of the Mini Museum as St. Cuthbert was a 7th-century monk on the island of Lindisfarne off the coast of Northumberland. If you’ll recall, the Vikings raided this island in 793 just 100 years after the death of St. Cuthbert, for whom the monastery there is named.

Above: Back of Specimen Card