Fig. 1. Changes in hydrocarbons of embryos and nymphs of B. germanica. Hydrocarbons of the ovaries and exterior and interior of the egg case (A), and exterior and interior of 40 first-instar nymphs (B) (the equivalent of one egg case) and 40 second-instar nymphs (C) were extracted and quantified by gas chromatography. Data are means ± s.e.m. (N=7). Some s.e.m. are obscured by the symbols. Significant differences among means in A are represented by different letters (ANOVA, LSD, P<0.05) and in B and C by asterisks (paired t-test, P<0.05).