The largest fruiting body is a giant puffball (Calvatia gigantea), which we can typically see in Ohio as a football-size or watermelon-size mushroom that can grow to 4 feet across and weigh up to 45 pounds or so.    From Wordnik.com. Reference

We apparently have some fairly knowledgeable mushroom fans around the county, because no less than three people wrote to let us know that the white fungus pictured in Monday's Summit Up was a giant western puffball, or Calvatia gigantea.    From Wordnik.com.  [Summit Daily News - Top Stories] Reference

At our class last week in Columbus, we came upon a little area in the woods with basketball-size snowy-white giant puffballs (Calvatia gigantea) and on Wednesday, the OSU Portage County Master Gardeners found a mass of small puffballs at Adell Durbin Arboretum in Stow, a great little park and arboretum where good friend Dave Roberts has tended the grounds for many years.    From Wordnik.com. Reference

The largest size was called the Giant Puff-ball (Calvatia bovista).”.    From Wordnik.com.  [Among the Mushrooms A Guide For Beginners] Reference

Calvatia (Cal-va'ti-a), 209.    From Wordnik.com.  [Studies of American Fungi. Mushrooms, Edible, Poisonous, etc.] Reference