The variations of amylase and of the ratio amylase/chymotrypsin (A/C) in the extracts of sea anemones are considered as correlated with the amount of microalgae and vegetal detritus in their diet. The results given by the lots of sea anemones from different depths did not fluctuate significantly for chymotrypsic activities, but the level of the amylolytic activity and the value of the ratio A/C varied as depth. The value of A/C was high in the extracts of sea anemones trawled from 2,000 m in the Bay of Biscay in June (84 plus or minus 52) and lower in September (36 plus or minus 16). The values measured in the extracts of sea anemones trawled from 5,200 to 4,500 m (off Portugal) in June, or from 4,900 m (in Demerara Plain) in September were remarkably low (21 plus or minus 3 and 15 plus or minus 10). The hypothesis of seasonal variations in the diet of deep-sea actinians was discussed.