Mortalities among seed and market oysters (Crassostrea virginica) were noted in June in lower San Antonio Bay, They occurred at a later period, and were less severe, in Espiritu Santo Bay. Upper San Antonio Bay did not appear to be affected. The nature of the mortalities was similar to that caused by "Aransas Bay disease" but the organism responsible was not identified. The oyster harvest was confined to small reefs in the upper bay area adjacent to Guadalupe Bay. Production appeared to be about one-quarter less than that of the previous season.