The Probert Encyclopaedia of Nature

ECHINUS

The Echinus (Sea-Urchins or Sea-Eggs) are a genus of marine animals, the type of an order (Echinoidea) of the class Phylum Echinodermata. The body is more or less globular and covered with a test or shell, often beset with movable spines. Locomotion is effected by a singular system of ainbulacra or 'tube-feet', which are distended with water, protruded through pores, and again retracted. The mouth is situated on the inferior surface, generally in the centre, is armed with calcareous teeth, and opens into a gullet conducting to a distinct stomach. The stomach has issue into a convoluted intestine which winds round the interior of the shell and terminates in a distinct anus. The anus varies in position, being sometimes on the apical disc and sometimes marginal. The Echinus esculentus and some other species are edible.
Research Echinus