This is a rare and important fossil of a water scorpion (eurypterid).
It was discovered around 1830 on what is now one of the best-known fossil sites in the world.
Hibbertopterus is also affectionately known called Scouler's Auld Heid (Old Head) after its discoverer. And because of its supposed resemblance to a human face.
Only the head, two body segments and some of the legs are preserved on this specimen.
Water scorpions are extinct relatives of today's scorpions, spiders and horseshoes crabs. Hibbertopterus grew to 1.5 metres long.
Despite its fearsome appearance, it fed on small animals sifted from the water. Fossil trackways suggest that it could also walk and survive on land.
Fossil water scorpion (Hibbertopterus scouleri)
Carboniferous Period, 335 million years ago
East Kirkton Quarry, Bathgate, Scotland
Size 190mm x 180mm
Given by Glasgow and West of Scotland Technical College