Fig. 1. Concentrations of metabolic substances in the haemolymph of Parastacus varicosus. Females: black bar; Males: white bar. The columns show the mean;
vertical bars show the standard error of the mean. The number of animals used was: in winter, 22 males and 14 females; in spring, 22 males and 14 females; in summer,
7 males and 4 females; and in autumn, 11 males and 4 females. The different letters indicate significant differences (capital letters for females and small letters for
males) ( pb0.05).