Sea urchins II: Worldwide irregular deep water species
Schultz, H. (2009). Sea urchins II: Worldwide irregular deep water species. Heinke & Peter Schultz Partner Scientific Publications: Hemdingen. ISBN 3-9809868-3-7. X, 501-849 pp.
Continues:
Schultz, H. (2006). Sea urchins: A guide to worldwide shallow water species. Third edition. Heinke & Peter Schultz Partner Scientific Publications: Hemdingen. ISBN 3-9809868-2-9. XII, 484 pp., more
Continued by:
Schultz, H. (2011). Sea urchins III: Worldwide regular deep water species. Heinke & Peter Schultz Partner Scientific Publications: Hemdingen. ISBN 3-9809868-4-5. 861-1338 pp., more
Sea Urchins II is the logical extension of the first volume, which dealt mainly with shallow water sea urchins. The second volume describes about additional 270 irregular species, which live in deeper water.
