Echinoids are ocean dwelling lifeforms which also include crinoids, brittle stars and star fish. They have lived on earth since the Ordovician period, over 450 million years ago and are still alive today. Their bodies are mostly circular in shape, though some are also heart shaped and some even have protrusions which look like fingers. They also vary in thickness, some being only a few mm thick while others are so thick, they are almost spherical. Patterns are sometimes observable on the bodies too. These blister packs contain a regular echinoid dated to the Jurassic period and found in Morocco, though they can be found almost all over the world. The packs are easy to open and re-seal and come with a x 4 magnifier lens and an information card.