Can't Un-Install rear Seats??

[sideshow775]

Hey . I have read the other post about removing the rear seats but they don't match my car. they said that there would be two bolts on both sides of the car right in the bottom corner when I moved the back rest down. But With my 92 civic hb I only have these black things that spin around. How do I remove the rear seats could anyone tell me? Thanx a lot