The spam was getting hard to keep up with, so I have made a minor change to the settings.
Posts appear here after you send them to an e-mail address that includes a string of numbers. I have made a change to that number: the last digit is now "1" instead of "0". Everything else remains the same.
I am hoping this will fix the problem. A spammer is auto-generating posts, most likely because the e-mail address is in someone's address book, but it's also possible that there is a problem with this Blogger account and if that's the case I'm not sure how to reclaim it.
This is the first post using the new string of numbers. Crossing my fingers...