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CACTACEAE, the Cactus Family 



Fleshy, jointed, leafless plants, armed with numerous thorns; 

 flowers large (510 cm. wide), yellow, with about 10 petals and nu- 

 merous stamens. 



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; re- 

 ceptacle cup-shape or tubular, bearing the 5 7 petals and sepals at 

 its margin, and the 6 12 stamens on its inner surface; ovary su- 

 perior. 



la. Stem shrubby (aquatic, stems 1 3 m. long; flowers pink, sum- 

 mer) Water Loosestrife, Decodon verticillatus. 



Ib. Stem herbaceous (4 10 dm. high; flowers purple, summer) 2. 



2a. Flowers solitary in the axils; leaves mostly alternate 



Loosestrife, Lythrum alatnm. 

 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, Khexia virginica. 



