A comtesse should be addressed by her surname, with the addition of madame: thus, "Madame de Montpellier" by the upper classes, and as "Madame la Comtesse" by all other classes.
A vicomte should be addressed by his surname, with the addition of monsieur: thus, "Monsieur de Toulouse" by the upper classes, and as "Monsieur le Vicomte" by all other classes.
A vicomtesse should be addressed by her surname, with the addition of madame; thus, "Madame de Toulouse" by the upper classes, and as "Madame la Vicomtesse" by all other classes.
A baron should be addressed by his surname, with the addition of monsieur: thus, "Monsieur d'Avignon" by the upper classes, and as "Monsieur le Baron" by all other classes.
A baronne should be addressed by her surname, with the addition of madame: thus, "Madame d'Avignon" by the upper classes, and as "Madame la Baronne" by all other classes.
A young unmarried lady should be addressed as "Mademoiselle d'Avignon" by the upper classes, and as "Mademoiselle" by all other classes.
In German titles the distinction of "Von" before the surname is seldom used colloquially, the title and surname being used without the prefix of "Von." Thus, "Count von Ausberg" should be addressed as "Count Ausberg" in conversation, and not as "Monsieur le Comte."
Foreign ladies of rank should be addressed by their title and surname, and not by their title only, and the prefix "Von" should be omitted; but in the case of a French or Italian title the "de" or "de la" before the surname should on no account be omitted.
When Englishmen are extremely intimate with foreigners of rank they would, in conversation, probably address them by their surnames; but only thorough intimacy and friendship warrants this familiarity.