A brief history and some fundamentals / Craig M. Young -- Phylum Porifera / Manuel Maldonado and Patricia R. Bergquist -- Phylum Cnidaria / Vicki J. Martin and Ron Koss -- Phylum Ctenophora / Mark Q. Martindale -- Phylum Platyhelminthes / Nancy F. Smith, Kevin B. Johnson, and Craig M. Young -- Phyla Dicyemida and Orthonectida / Hidetaka Furuya -- Phylum Nemertea / Jon L. Norenburg and Stephen A. Stricker -- Phylum Loricifera / Reinhardt M. Kristensen and Sandra Brooke -- Phylum Priapulida / Thomas Shirley -- Phylum Acanthocephala / Nancy F. Smith -- Phylum Cycliophora / Reinhardt M. Kristensen and Peter Funch -- Phylum Annelida : Polychaeta / Bruno Pernet ... [et al.] -- Phylum Mollusca : Polyplacophora, Aplacophora, Scaphopoda / John Buckland-Nicks, Glenys Gibson, and Ron Koss -- Phylum Mollusca : Gastropoda / John Buckland-Nicks, Glenys Gibson, Ron Koss -- Phylum Mollusca : Bivalvia / John D. Zardus and André L. Martel -- Phylum Mollusca : Cephalopoda / Michael Vecchione and Elizabeth K. Shea -- Phylum Arthropoda : Crustacea / Alan W. Harvey, Joel W. Martin, and Regina Wetzer -- Phylum Echiura / John F. Pilger -- Phylum Sipuncula / William B. Jaeckle and Mary E. Rice -- Phylum Entoprocta / Claus Nielsen -- Phylum Bryozoa / Michael H. Temkin and Russel L. Zimmer -- Phylum Phoronida / Kevin B. Johnson and Russel L. Zimmer -- Phylum Brachiopoda / J. Timothy Pennington and Stephen A. Stricker -- Phylum Echinodermata : Crinoidea / Elizabeth J. Balser -- Phylum Echinodermata : Ophiuroidea / Maria Byrne and Paulina Selvakumaraswamy -- Phylum Echinodermata : Asteroidea / Larry R. McEdward, William B. Jaeckle, and Mieko Komatsu -- Phylum Echinodermata : Holothuroidea / Mary A. Sewell and F. Scott McEuen -- Phylum Echinodermata : Echinoidea / Richard B. Emlet, Craig M. Young, and Sophie B. George -- Phylum Hemichordata / Michael G. Hadfield -- Phylum Chordata : Urochordata / Richard A. Cloney, Craig M. Young, and Ib Svane -- Phylum Chordata : Cephalochordata / Daniel A. McCarthy and Craig M. Young.