Fig. 3. Temporal pattern of in vitro ferrous iron (Fe²⁺; filled symbols) and ferric iron (Fe³⁺; open symbols) absorption at a concentration of 0.2 µmol l^–1 iron in the three regions of the intestine of the European flounder; anterior (, ), mid (, ) and posterior (, ). Values are means ± S.E.M. (N=3–4). An asterisk indicates a significant difference between the absorption of Fe³⁺ and Fe²⁺ at a particular time (Student’s t-test, P<0.05), and values with differing letters indicate significant differences between Fe²⁺ absorption of the three regions at the 400 min incubation point (ANOVA followed by an LSD test, P<0.05). There are no significant difference between Fe²⁺ absorption of the three regions at the other time points.