Fig. 1. Effect of inhibition of carbonic anhydrase on the pH of culture medium of fourth-instar larvae of Aedes aegypti. Mosquito larvae typically alkalize the medium in which they are reared (Stobbart, 1971). (A) Six culture wells each containing five fourth-instar larvae incubated for 5 h in medium containing 0.003 % Bromothymol Blue. The blue color is retained, indicating a pH greater than 7.6. (B) The same as A, except that each well also contains a different concentration of the specific carbonic anhydrase inhibitor methazolamide ranging from 10^–6 to 10^–3 mol l^–1 from left to right. A yellow color indicates a pH below 7.6.