Across
- 5. spherical or flattened bodies
- 6. cup-like calyx and feathery arms
- 9. spiny endoskeleton, radial symmetry
- 11. Threat to echinoderm populations
- 12. Hard plates
- 14. expels sticky threads or toxins
- 15. Cup-like structure
- 16. Hard plates
- 18. Sieve-like opening
- 19. graze on algae and detritus
Down
- 1. elongated bodies and leathery skin
- 2. Flexible, fluid-filled
- 3. filters plankton
- 4. disturbance
- 7. regrow lost body parts
- 8. five-fold radial symmetry
- 10. hydraulic system in echinoderms
- 13. central disc and long, slender arms
- 17. central disc and radiating arms