Seed head

This is a very strange plant I saw growing in a vacant house garden today. The head was like a large ball, bigger than a tennis ball. It was among other herbs that had gone to seed. Any ideas on what it is?

Dave and I had a lovely night - drinks and a seafood platter at the Dux de Lux and then a trip to the library - bought home a big pile of books.

Am finally starting to get over my cough. Last night had my first good night's sleep in 2½ weeks.