Photomicrograph of sagittal histological sections of cornea of Clarias gariepinus: (1) control showing normal stratified epithelium, Bowman’s layer, heavily nucleated stroma, Descemet’s membrane and endothelium;(2–3) bright light exposed group showing damaged epithelium and fragility of stroma; (4–5) dim light exposed group showing less improved stroma. Arrow head refer to vacuolization. Arrow refers to pyknosis. Crossed arrow refers to epithelial cell loss. Star refers to stromal edema. (Ep) Epithelium, (BM) Bowman’s membrane, (St) stroma, (DM) Descemet’s membrane, (E) endothelium, (NL) normal light, (BL) bright light, (DL) dim light.