Autumn Parasol.....

I set off at lunchtime for a spot of fresh air and within a few feet of the building where I work this is what I found. It's the size of an average dinner plate and reminded me of the type the caterpillar in Alice in Wonderland would have sat on.

If anyone can let me know exactly what funghi this is I'd be very grateful? I think it's a Parasol Mushroom but I don't know which one?

I'm not looking for more funghi, I just keeping seeing them everywhere!