After checking the wiki article, it certainly looks like it could be the Big Sheath Mushroom:
https://en.wikipedia.org/wiki/Volvopluteus_gloiocephalus
I looked this one up in Mushrooms Demystified, too. Does it have a sac-like cup at the base? Is the spore print pinkish? Does the stem lack a ring? If the answer is yes to these three questions, I think you have some Big Sheath Mushrooms. Although listed as edible, certainly not worth it. My rule is never eat any wild mushrooms from internet ID alone. There have been several fatalities where immigrants mistook white Amanita mushrooms for relatives of the Big Sheath Mushroom.
And in case the spores are white and you might have an Amanita of some kind, I would not worry about getting poisoned by handling them or inhaling spores. Just don't eat them!!