Examination of 144 samples of seed potatoes affected with dry rot, comprising 1218 tubers, showed the presence of parasitic Fusaria in 91% of the lesions. The parasitic Fusaria consisted of 93%Fusarium caeruleum, 6%F. avenaceumand less than 1% each ofF. arthrosporioidesandF. tricinctum. F. tricinctumhas not previously been recorded on potato in this country.A method is described whereby the presence ofF. caeruleumcan readily be detected in tubers affected with dry rot.