She is not "Princess Diana.You perhaps know the lady Miss Manners means -- the blond one who wears hats so nicely but has not always managed to keep her hair out of her eyes; the one who seems to attract so much attention.

Born a commoner, she was styled "Lady Diana" by courtesy because her father is an earl. She is now, having married up, "the Princess of Wales." Only should she become queen consort would a royal title appear before her first name, as "Queen Diana."

Is that clear?

Of course not. We Americans decided long ago that the idea of classifying some people as, by virtue of birth or marriage, belonging to a higher order of humanity than their fellow citizens was not for us. Our highest title is "Mr.," as in "Mr. President," and it takes the individual some doing to get it.

But the British do show up on our shores now and again, and mild interest is taken in their wardrobes and other appurtenances, so one may want to know their usage. Besides, it is difficult to make one's way through 19th-century British novels or 20th-century British television without being able to figure out who is called what and why.

The subject is infinitely complicated, and disputes have been known to last for centuries. Miss Manners will concern herself only with the basic outline.

Only the reigning queen and her mother (as the widow of the previous king) are addressed as "Your Majesty," other members of the royal family being addressed as "Your Royal Highness." Children of the sovereign also use the prefix "the," as in "Their Royal Highnesses, the Prince and Princess of Wales."

The peerage has five grades: duke (not to be confused with royal dukes), marquess (most use the good old English spelling rather than the French "marquis"), earl, viscount and baron. The female equivalents, for wives or widows (the latter styled dowager, if the succeeding peer has a wife) are: duchess, marchioness, countess, viscountess and baroness. There are also countesses and baronesses in their own right.

Except for dukes and duchesses, who are called by those titles, peers and peeresses are addressed as "Lord" or "Lady" with the name of the senior peerage they possess.

Legally, the children of these people are all commoners.

However, dukes, marquesses and earls tend to have other titles as well, and by courtesy, their sons-and-heirs-apparent (as opposed to an heir presumptive, who is heir but not son to someone who is still presumed, sometimes by courtesy, to be able to produce a son) use the next family title down until after, courteously enough, the funerals, not the deaths, of their fathers.

Younger sons of dukes and marquesses are styled "Lord" before their given names and family surnames (which are apt to be different from the peerage name), dropping the surname on second reference. Their wives use the husbands' given names, rather than their own, with "Lady."

Daughters of dukes, marquesses and earls have the courtesy title of "Lady" preceding their given names and surnames, keeping the designation if they marry and change their surnames.

The younger sons of an earl, and all sons and daughters of viscounts or barons, are styled "The Hon." before their full names, but that designation is never used except on envelopes and by the formidable Mitford girls -- when they were girls, rather than writers and duchesses.

Then there are titled commoners: baronets, whose degrees of honor are hereditary, and knights, whose are not. They use "Sir" before their full names, but are addressed with the title and given name only. Their wives use "Lady" with the surname only, never with their given names (a common American error) unless they happen also to be the daughters of dukes, marquesses or earls.

This is only the beginning. Miss Manners will not bore you with collateral privileges of the siblings of heirs presumptive who succeed, the rights of duchesses who were divorced in interesting trials, the children of peers who disclaimed their peerages, and so on.

She only asks you to stop saying "Princess Diana." And never mind that British newspapers do it all the time. Wherever did you Americans get the notion that the British always behave properly?Q When visiting friends or relatives, not merely a drop-in-and-say-hello occasion, is it necessary, advisable and proper to ask permission of the hostess to use the bathroom, especially when you know where that certain room is located?

When it cannot be done discreetly, asking permission seems like announcing to all present that you have to go. But I have seen an almost offended look on the face of a hostess when I returned from an "unauthorized" visit. A "May I use the bathroom?" is an idiomatic expression, not to be taken literally. Miss Manners has never heard of a hostess' refusing permission.

Unless you were bypassing a guest bathroom to use one the hostess had not intended to be available, surely you must be mistaken in assuming that she wished to be consulted as to whether you could use her bathroom. Considering the consequences for the premises, this would be not only mean, but foolish.

The true meaning of the question is: "Would you be so kind as to show me where the bathroom is?" Familiar visitors, who know where it is, need only say, "Excuse me."