will probably be clarified by the continued cooperative efforts of
scientists such as those in the group that met in Berlin last September.
The staff of Dahlem Konferenzen is responsible for making the meeting of
this group memorably pleasant and pleasantly mem- orable. Dr. Bernhard's
gifts of charm, organizational skill, and administrative toughness
assured that the conference was run elegantly, smoothly, and decisively,
even down to the choice of editors for this volume. Marie
Cervantes-Waldmann performed minor miracles extracting manuscripts
gently but persistently from the authors and in turning the typescripts
into a book. The other staff members of Dahlem Konferenzen were
unfailingly helpful even under trying circumstances. They will be well
rememberedbyall who were fortunate enough to be asked to Berlin for the
first week in September, 1980. Mineral Deposits and the Evolution of the
Biosphere, eds. H. D. Holland and M. Schidlowski, pp. 5-30. Dahlem
Konferenzen, 1982. Berl in, Heidelberg, New York: Springer-Verlag.
Microbial Processes in the Sulfur Cycle Through Time H. G. TrUper
Institut f. Microbiologie, Rheinische Friedrich-Wilhelms-Universitat,
5300 Bonn 1, F. R. Germany Abstract. Two microbial processes are
involved in the sulfur cycle of the earth's biosphere: anoxic
dissimilatory sulfur oxidation by phototrophic bacteria and
dissimilatory sulfate reduction by sulfate-reducing bacteria. In the
presence of oxygen at chemoclines and redoxclines dissimilatory sulfur
oxidation by chemolithotrophic bacteria (Thiobacillus, Beg- giatoa, and
others) occurs. In addition, dissimilatory sulfur reducing bacteria
participate in the sulfur cycle.