The 24-h LC50 of these two species are two or three orders of magnitude lower than those reported for crustaceans and dipterans (Martin and Holdich, 1986; Williams et al., 1986; Khangarot and Ray, 1987).
The 24-h LC50 of these two species are two or three ordersof magnitude lower than those reported for crustaceans anddipterans (Martin and Holdich, 1986; Williams et al., 1986;Khangarot and Ray, 1987).