Asterias, many times enlarged, made in SOMSO-Plast®. After Studiendirektor Christian Groß. The model shows in detail: 1. Complete arm with normal position of the organs (stomach, intestinal caeca, pyloric caica, ampullae). 2. Arm with ampullae, ring canal, Polian vesicles. 3. Skeleton of the arm with nervous system (nerve-ring and radial nerves). 4. Arm in transverse section (ambulacral system in cross-section). The cut surface shows the stomach, stone canal, axial organ and madreporite. In addition on the outside the podia, pedicellariae and optic organs are shown. The model can be taken from its stand. Altogether in 3 parts. On a stand and green base.