Basicities of nine dimethylanilines have been determined in 50, 70, and 90 volume % ethanol, at $25^{circ},;30^{circ},;35^{circ},;and;40^{circ}C$. Temperature coefficients were found to be independent of solvent composition, while they showed a linear correlation with basicities of the compounds. Thermodynamic parameters obtained have been used in the discussion of substituent and solvent effects in conjunction with the general equation derived in the preceding papers.