Figure 4. Total cuticle thickness.

Box plots (box boundaries = the 25^th and 75^th quartiles, error bars = 1.5 times the interquartile distance, center line = median, diamond = mean) illustrate that no significant differences in mean total cuticle thickness in mm divided by carapace length in mm (to correct for body size) were detectable between treatments either within the (a) carapace or (b) merus or between the three- and six-month exposure periods (N = 111). Black dots represent outliers from the box plots, but values were included in the analysis because there were no obvious biological reasons to exclude them.