Figure F7. Total prokaryotic cell numbers per cubic centimeter (solid circles) and the percentage of cells indicating cell division (open circles) with depth at Site 1226. Vertical dashed line represents the detection limit at 5.6 × 104 cells/cm3. Dividing cell percentages become increasingly unreliable as total cell counts decrease below 106 cells/cm3 as within-sample variability rises due to the low number of cells counted. Samples with cell concentrations below the detection limit are arbitrarily shown as containing 1 x 104 cells/cm3.