This section is from the book "Harper's Guide To Wild Flowers", by Caroline A. Creevey. Also available from Amazon: Harper's Guide To Wild Flowers.
Family, Saxifrage. Color, white. Calyx, tubular, top-shape, the limb 4 to 5-parted. Petals, 4 or 5, roundish or ovate, large, not scented. Stamens, numerous. Styles, 3 to 5, more or less united. Flowers, generally 2 or 3 together, terminating short branches; sometimes single. Leaves, opposite, oval, pointed at both ends, distinctly 3-nerved, entire around the margins, or with a few small teeth. May.
In thickets south of Virginia. Cultivated in Pennsylvania and escaped from gardens.
 
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