This mushroom was found on the grass just off a sidewalk while walking my dog near my house. The cap is parabolic shaped, with an even margin. The cap surface is smooth. The partial veil appears superonate. The gills appear close from what I can tell. The bulb looks cleft-like.
It resembles the Field Mushroom, Agaricus, due to its round shape. If I took a better picture of the bottom I would more easily be able to tell.

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