Dear Miss Manners: I regularly frequent a fairly informal pizza chain, as I like their lunch special. I was sitting at the bar yesterday when my food came; I took a bite of pizza and then saw, in between the salad and pizza, a dead bug.

It was bigger than a fruit fly, but not huge. A work call came in, so I took about five minutes to deal with that, and then waited for the server/bartender, and finally went over to talk to her.

I know intellectually the bug wasn't a huge deal, but because I spent several minutes with it on my plate, upside down with the legs in the air, I just didn't have an appetite. I quietly told the server that I understood that it wasn't her fault, but I had a bug on my plate and wasn't going to be eating any more lunch.

She said she was sorry and took the plate away, and I left. I told my boyfriend about it later, and he, just like the server, seemed to be surprised that I got up and left.

What's the proper etiquette in that situation? If you go to a sit-down restaurant and see something like that after having taken only one bite, is it OK to leave, or is that bad form? Should I have given the restaurant another chance?

I go pretty often (once a week) and tip well, usually 50 percent. I also just didn't have an appetite after that, which was very disappointing because I had been hungry and love pizza.

But I didn't mean to be impolite, and I didn't make a scene. I was as quiet as possible because I didn't want the other people at the bar to hear.

Gentle Reader: Another chance to do what, exactly? Clean the kitchen?

Miss Manners appreciates your concern for the restaurateur's feelings, but assures you that good manners do not require you to take a chance on a replacement meal. An astute server — not to mention her boss — should have been all over you with apologies and restitution out of concern that you would call the local health department. Which, by the way, might be a good idea.

Feeling faint

Dear Miss Manners: When an expecting mother is out in public — for instance, in the waiting area of a casual restaurant — where all the seating is taken and she begins to feel a little unsteady on her feet, would it be appropriate for her to ask a man who is sitting down if she might borrow his seat for a few minutes? Or must she leave the restaurant to find somewhere to sit down?

Gentle Reader: Even in a formal restaurant, Miss Manners would think that any gentleman would happily give up his seat, if only to avoid the glares that would follow from those watching a pregnant lady passing out on the floor in front of him.

"Miss Manners" is Judith Martin of the Washington Post. Send questions to her website, www.missmanners.com.