It is proposed that the Judicial Commission of the International Committee on Systematic Bacteriology conserve the specific epithet liquefaciens over the specific epithet proteamaculans in the scientific name of the organism currently known as Serratia liquefaciens (Grimes and Hennerty 1931) Bascomb et al. 1971. Although the name Pseudomonas proteamaculans was applied to what may be the same organism and was validly published by Paine and Stansfield in 1919, the name remained obscure until the only extant strain, claimed to originate from the collection on which Paine and Stansfield based their description of P. proteamaculans, was found by Grimont et al. in 1978 to be identical with S. liquefaciens biotype C1c. Meanwhile, the name Serratia liquefaciens has gained worldwide acceptance. To stabilize the nomenclature and to avoid confusion in the literature, the specific epithet liquefaciens should be retained in the name of this organism.