We have prepared a modification of Rappaport's medium by reducing the content of themalachite green oxalate: medium R10, which is incubated at 43 degrees C instead of 37 degrees. These two modifications allow a satisfactory growth of a wide range of Salmonella and a better inhibition of competing organisms than the original medium of Rappaport incubated at 37 degrees and than Muller-Kauffmann's medium incubated at 43 degrees.