Figure 1.

The frequency distributions (n = 20) of developmental stages attained by X. laevis tadpoles after the 21-day exposure to graduated concentrations of Midstream formulation relative to the control (Figure 1). The upward arrow showed the median NF-stage at the control relative to downward arrow that showed the median at the exposure concentrations. The asterisk showed significant difference (P < 0.05) relative to the control.