The orthoceras lived about 400 million years ago and is the precursor of our current squid.
Right horn from prehistoric times
Orthoceras means 'straight horn' referring to the long straight shell of the animals. The soft part was inside the shell and its protruding tentacles allowed it to move. When the animal died, the shell sank to the bottom where it was covered by sediment, so the shell fossilized and it has been preserved for us even after 400 million years.
Related to the squid
The Orthoceras was related to today's squid and could also spray ink for defense. They occurred all over the world. The most beautiful orthoceras are found in the Atlas Mountains, just like this one.