This photo is from early May in Dr. Whiteside’s garden, and as it turns out, it is not native to New England. I think it’s a rare variety native to parts of the Appalachian mountains in the southeastern United States. Lily family.
Sweet Trillium, Jeweled Wakerobin, Confusing Trillium (Trillium simile)
Here are a couple more shots from that day, also of some varieties not wild in New England: some very fragrant and unexpectedly pink! lilies of the valley, and a variety of Lady’s Slipper (Cypripedium). There are 11 species of Lady’s Slipper native to the U.S., but I think this one might be a hybrid instead of a wild variety. (Cypripedium: Cypri- refers to the island of Cyprus, where Aphrodite was born, and -pedium means shoe or foot.)