Fig. (2) Photomicrographs of T.S. of midgut epithelium of early fourth instars of Aedes aegypti. a) Exposed to negative control (ethanol alone) in control experiment; b) Exposed to positive control (permethrin); Epithelial cells (Ep), Nucleus (N), Food bolus (FB), Peritrophic Membrane (PM), and Basement Membrane (BM) * Magnification: 40X