A.H.H. Stephens and M.L.H. Green, Organometallic Complexes of the Fullerenes. T. Saito, Group 6 Metal Chalcogenide Cluster Complexes and Their Relationships to Solid State Cluster Compounds. M.P. Suh, Macrocyclic Chemistry of Nickel. K.A. Francesconi and J.S. Edmonds, Arsenic and Marine Organisms. H.B.F. Dixon, The Biochemical Action of Arsonic Acids Especially as Phosphate Analogues. E. Kimura and T. Koike, Intrinsic Properties of Zinc(II) Ion Pertinent to Zinc Enzymes. C. Bianchini and R.W. Zoellner, Novel Aspects in the Activation of Dioxygen by Cobalt Group Metal Complexes: A Critical Review of Recent Developments. D.A. House, Recent Developments in Chromium Chemistry. ChapterReferences. Subject Index. Contents of Previous Volumes.