Of 532 strains of viridans streptococci isolated from clinical specimens, 517 were identified by using a scheme based on the work of Facklam (R. R. Facklam, J. Clin. Microbiol. 5:184-201, 1977). The strains were distributed among nine of the species described by Facklam and an additional group of physiologically homogeneous streptococci not recognized in Facklam's scheme. The method for identif...