SUMMARY

The native DNAs of both carnation etched ring virus (CERV) and figwort mosaic virus (FMV) formed multiple bands on gel electrophoresis thus resembling cauliflower mosaic virus (CaMV) DNA; there were some minor differences in banding patterns. Denaturation and nuclease $1 digestion showed that CERV DNA had three discontinuities (two in one strand and one in the other) and FMV DNA had four discontinuities (three in one strand and one in the other). These discontinuities and the sites of restriction endonuclease digestion were mapped on CERV and FMV DNAs and the maps compared with those of CaMV DNA. The maps of the three virus DNAs were very different