1. Editorial

   • Peter Hirsch

   EditorialNotes Pages: 1 - 2

2. Measurement of bacterial growth rates in subsurface sediments using the incorporation of tritiated thymidine into DNA

   • Patti M. Thorn
   • Roy M. Ventullo

   OriginalPaper Pages: 3 - 16

3. Microbial communities in the saturated groundwater environment I: Methods of isolation and characterization of heterotrophic bacteria

   • Jutta Kölbel-Boelke
   • Birgit Tienken
   • Alexander Nehrkorn

   OriginalPaper Pages: 17 - 29

4. Microbial communities in the saturated groundwater environment II: Diversity of bacterial communities in a Pleistocene sand aquifer and their in vitro activities

   • Jutta Kölbel-Boelke
   • Eva -Maria Anders
   • Alexander Nehrkorn

   OriginalPaper Pages: 31 - 48

5. Morphological and cultural comparison of microorganisms in surface soil and subsurface sediments at a pristine study site in Oklahoma

   • T. L. Bone
   • D. L. Balkwill

   OriginalPaper Pages: 49 - 64

6. Investigations into the number of respiring bacteria in groundwater from sandy and gravelly deposits

   • Jürgen Marxsen

   OriginalPaper Pages: 65 - 72

7. Equivalence of microbial biomass measures based on membrane lipid and cell wall components, adenosine triphosphate, and direct counts in subsurface aquifer sediments

   • David L. Balkwill
   • Franklin R. Leach
   • David C. White

   OriginalPaper Pages: 73 - 84

8. Distribution and activity of microorganisms in subsurface sediments of a pristine study site in Oklahoma

   • Ronald M. Beloin
   • James L. Sinclair
   • William C. Ghiorse

   OriginalPaper Pages: 85 - 97

9. Some special problems in the determination of viable counts of groundwater microorganisms

   • P. Hirsch
   • E. Rades-Rohkohl

   OriginalPaper Pages: 99 - 113