I just found a mushroom in my yard today, and I tried looking online to see what it was, and found some similar to it, but not exactly like it. I'm concerned because we let our dog out to play around the area where it popped up, and my son also likes to play outside. I am wondering if they are poisonous or harmless. We live in Biloxi, in an area that was flooded a small amount from Katrina, so I was thinking maybe it waswashed in from somewhere else? I don't know anything about mushrooms except the kind you buy in the store.