A Reliable Method for Demonstrating Gram-Positive and Gram-Negative Bacteria

Combined Gram techniques have been reviewed in the interest of improving technical safety and reliability in the demonstration of bacteria, particularly the Gram-negative type. The many modifications of the technique present various difficulties (Brown and Brenn 193 1, Humberstone 1963, Taylor 1966, Luna 1968, Brown and Hopps 1973, Engbaek et al. 1979, Bancroft and Stevens 1982, Churukian and Schenk 1982).