- The statistical significance for the Student’s
*t*-test (*blue*) indicates that the deviation from the mean of stained somata within 20 μm thick sections of the leg-bearing region (seven sections) differs significantly (***, *p* < 0.001) from the deviation of the mean of stained somata within the interpedal region (nine sections). The statistical significance for the χ^{2}-test (*green*; *, **, ***, ****, *p* < 0.05, 0.01, 0.001, 0.0001, respectively) indicates that the distribution of stained somata within the ten portions of one hemisegment differs significantly from a theoretically expected uniform distribution with no regional specialisation in the nerve cord. df, degrees of freedom for the test; n.s. not significant; *p*, probability of error