Fig. 5. Ratio of [Glycerol] in tissue (µmol ml^–1 tissue water)/plasma (µmol ml^–1 plasma) in rainbow smelt Osmerus mordax subjected to a controlled decrease in water temperature. The date at which a controlled temperature decrease was initiated (i.e. 15 January 2004) was used as day 0. The broken line represents equal values for glycerol in tissue water and plasma. Asterisks indicate values significantly different from 1.0. Water temperature (°C) on each sampling day is shown on bottom panel in parentheses. Values are means ± s.e.m., N=4 for all points.