Nine species of fungi are known to occur on various species of Synedra (Sparrow, 1960: 1086). Of these, Ectrogella perforans Peter? sen, E. licmophorae Scherffel, and E. eurychasmoides J. & G. Feldmann are known from strictly marine habitats, occurring in species of Licmophora. In 1962 and 1964 specimens of Synedra infected by fungi were collected in three brackish water areas of one North Carolina estuary. This paper reports these fungi. Inasmuch as two of the fungi occurred in a rather unusual habitat, a brief statement on major features of the collection sites is given. A more or less regular collection program for fungi in the Neuse River of Eastern North Carolina has been under way since 1955. In 1956, seven promi? nent station sites were established along a salinity gradient in this estuary. Monthly or bimonthy samplings for various fungi have been made since 1956, and in 1962 these same stations became the sites for either regularly or intermittently scheduled plankton tows. Salinity, temperature and pH of the waters at these stations have been determined at each sampling since 1956, and in the years 1958-1960, dissolved oxygen, nitrate and phosphate tests were also made. Thus, rather complete records of major environmental factors are extant. The fungi reported in this paper were each found once at one of three stations in the estuarine system. Flanner's Beach Station is near the uppermost reaches of the estuary. Salinity ranges here from 7.816.9%c, but predominates in the region of 8-11%C. Adam's Creek Station, some six nautical miles east of Flanner's Beach has had, in nine years, a salinity range of 7-23.1%0 (predominantly 12-17%c), while the Core Creek Station three nautical miles nearer the mouth of the estuary has had a somewhat higher range: ll-26.5%c, generally 18-23%c. Diurnal tidal cycles are evident at all three stations, but the highest amplitude is at Core Creek. Although Synedra species are to be found in the fresh-water sector of the river, they are not thus far known to be infected by fungi.