. R. Branch. Venom yields from three species of side-biting snakes (genus Atractaspis, Colubridae). Toxicon 19, 271-277, 1981.—Venom was collected from three species of Atractaspis (A. bibroni, A. dahomeyensis and A. engaddensis). Like viperid venoms and unlike elapid venoms, the majority of Atractaspis venom proteins migrate towards the anode in starch gel electrophoresis (pH 8.6). Venom yields per milking for A. bibroni (0-5-1-4mg dry weight) and A. dahomeyensis (0-85-1-00 mg dry weight) were substantially less than for A. engaddensis (4 1—9-6 mg dry weight). Dry weight of all venoms was 22-27% that of the wet weight An ld30 in mice of 2-24 mg/kg (95% confidence limits 1-49-3-39 mg/kg) was calculated for A. dahomeyensis venom. The clinical significance of these findings are discussed.