The Hook Peninsula is a very good place to get a glimpse of our ancient past. This is especially true in the low lying Carboniferous limestone around Hook Head and Slade. Crinoid and Bryozoan fossils are two of the most frequently encountered types here. These are over 300 million years old!
Crinoids, often called sea lilies due to their shape, were sea animals (relatives of the starfish) attached to the sea floor by a stem, with arms at the end used for sweeping the water for food. You have probably seen fragments of these animals in the rocks all around the hook; they look like small polo mints in the grey rock! 48 different species of crinoids have been recorded at Hook Head.
Bryozoans on the other hand were tiny sea animals which lived in colonies of net like structures known as sea-mats. The mat is the remains of the skeleton like structure that remains after the animals have died. Each hole in the net once housed an individual member of the colony.