The tiny spines that make up the body structure of animals of the peripheries phase are called spicules. It is composed of lime or silica. It is a hard material. Neptune Cup (Poterion neptuni).
Educational Website
The tiny spines that make up the body structure of animals of the peripheries phase are called spicules. It is composed of lime or silica. It is a hard material. Neptune Cup (Poterion neptuni).