Two hundred and eight strains of Brucella isolated from cattle and 5 isolated from man in various areas of France, during a two-year period from 1972 to 1974, were examined by all methods recommended by the Subcommittee on Taxonomy of the genus Brucella and were found to have the same characteristics that identify and define the species Brucella abortus. Of the 213 strains, 105 (49,29 p. 100) were biotype I, 103 strains (48,36 p. 100) biotype 3, three strains (1,41 p. 100) biotype 4 and 2 strains (0,94 p. 100) biotype 2. The distribution of Brucella abortus biotypes isolated from cattle and man in France is reviewed and compared with the data from our sample. It corroborates the epidemiologic importance of Brucella abortus biotype 3, just after type 1, and the absence of biotypes 5 to 9(1) in France. Five strains of Brucella abortus biotype 3, originating from a well-defined geographical area, are ureaseless. This new biochemical character distinguishes these strains from the main group of biotype 3 and is discussed from an epidemiological and methodological point of view. Data on the oxydative rates obtained on 12 substrates by the 213 strains are presented in graphic form which reveals a metabolic profile for the species Brucella abortus. The interest of this graphic presentation is discussed and its use should be recommended.