Fig. 6. (A) Comparison of the maximal amplitude of adrenergic response of 8 pairs of control and hydroxylamine (10^–3 mol l^–1) treated photophores. (B) Extinction time course for luminescence from adrenaline stimulated photophores. On addition of hydroxylamine (H, arrow), treated photophores show an acceleration of light extinction as compared with control photophores.