LIEUT.-COL. R. B. SEYMOUR SEWELL has made an interesting study of the fauna of the salt lakes of Calcutta (Rec. Ind. Mus., 36, Part 1. 1934). Recent changes in the general character of some of the rivers in Lower Bengal have had a profound effect on these salt lakes and their associated streams, indirectly influencing the general character of the fauna of certain areas, silting in the rivers and canals due to various causes being the main factor in these changes.