One species in Michigan, on the shores of Lake Michigan; flowers in summer =Prickly Pear, Opuntia rafinesquii.= THYMELAEACEAE, the Mezereum Family Shrubs, with simple alternate entire leaves, and small yellowish flowers in clusters, opening before the leaves; petals none, the sepals somewhat petal-like. One species in Michigan, 5-15 dm. tall, with very tough bark =Leatherwood, Dirca palustris.= ELAEAGNACEAE, the Oleaster Family Shrubs, with opposite, silvery-pubescent, simple, entire leaves, and small clusters of inconspicuous yellow flowers in spring. One species in Michigan, 1-2 m. high =Buffalo Berry, Shepherdia canadensis.= LYTHRACEAE, the Loosestrife Family Herbs or shrubs, with opposite or alternate entire leaves; receptacle cup-shape or tubular, bearing the 5-7 petals and sepals at its margin, and the 6-12 stamens on its inner surface; ovary superior. 1a. Stem shrubby (aquatic, stems 1-3 m. long; flowers pink, summer) =Water Loosestrife, Decodon verticillatus.= 1b. Stem herbaceous (4-10 dm. high; flowers purple, summer) --2. 2a. Flowers solitary in the axils; leaves mostly alternate =Loosestrife, Lythrum alatum.= 2b. Flowers in terminal panicles; leaves opposite or whorled =Loosestrife, Lythrum salicaria.= MELASTOMACEAE, the Melastoma Family Herbs, with opposite leaves with 3-5 principal veins; receptacle urn-shape, bearing 4 sepals and 4 petals at its edge; stamens 8; ovary 4-celled, superior. One species in Michigan, 3-4 dm. high, with purple flowers in late summer =Meadow Beauty, Rhexia virginica.= ONAGRACEAE, the Evening Primrose Family Herbs with opposite or alternate simple leaves and regular flowers; sepals and petals each 4 (or 2 in one genus), stamens 8 (or 2 in one genus), attached to the summit or inside of a tubular receptacle; ovary 2-4-celled, inferior. 1a. Aquatic plant of shallow water or muddy ground, with prostrate stem (flowers minute, axillary; petals small or none, summer) =Water Purslane, Ludvigia palustris.= 1b. Land plants with erect or ascending stems --2. 2a. Petals minute, greenish (3-8 dm. high; late summer) =False Loosestrife, Ludvigia polycarpa.= 2b. Petals yellow --3. 2c. Petals white, pink, purple, or red --9. 3a. Sepals borne at the summit of the ovary (5-10 dm. high; summer) =False Loosestrife, Ludvigia alternifolia.= 3b. Sepals borne at the summit of the slender tubular receptacle, which is prolonged beyond the ovary --4. 4a. Stamens all equal in length (Evening Primrose) --5. 4b. The alternate stamens longer (3-8 dm. high; summer) (Sundrops) --8.