On the old forum I tried to compile a list of every Genesis album track with who wrote the lyrics, I think we got pretty close but there's still a few I'm unsure about. They are:
Fountain of Salmacis (which I assume is Mike & Tony)
Can-utility and the Coastliners (which I think might be Steve?)
The Cinema Show (which is some combination of Tony, Mike and Peter)
Dance on a Volcano (which I have no idea about, I don't think it's ever been touch upon who wrote the lyrics, my guess would be Mike or Tony)