But I did end up taking her over to Adobe, because she started straining again and didn't produce a kitten within the half hour, as the cat pregnancy site suggested she should. They x-rayed her and found one last huge kitten, which they helped her deliver. Also stillborn :(

I'm not feeling too adequate as a kitten foster mother! Though I couldn't have done anything for the first two, as they were born while I wasn't there; I rubbed them down and cleared their mouths, just in case, but they were pretty clearly beyond help. Maybe the last one, if I had taken her in before she tried to deliver it.

The grey and black kittens were pronounced healthy and vigorous, however, and she's in a box in the spare room with them.