The adsorption isotherms of c'yanine dyes Ⅱ and Ⅲ (1-methyl-1'-(γ-sulfopropyl)-2,2'-cyanine Ⅱ and its 6' -methyl analog Ⅲ) on AgBr suspensions in several solvents were obtained at 25℃ by centrifugation method. Corresponding absorption (reflection) spectra of these dyes in solutions and in adsorbed states over a wide concentration range were recorded. The solvent effect on dye adsorption and on the aggregation states of dye molecules were discussed. The very small heat effect in dye adsorption was measured a...