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NORTH AMERICAN FLORA 



[Volume 25 



Androeciuni of 5 or 6 stamens ; style single. 

 Samara winged ; sepal-glands elongate. 

 Samara keeled ; sepal-glands short. 

 Fruit bristly. 



Gynoecium with a single style ; calyx glandless. 



Style slender, not tapering ; stigma 2-lobed ; filaments glabrous. 

 Style stout, tapering ; stigma entire ; filaments pubescent. 

 Gynoecium with 3 styles ; calyx with stalked glands. 

 Receptacle flat or depressed ; fruit a drupe, a capsule, or nut-like. 

 Fruit separating into 3 carpels or capsules. 

 Styles thick-tipped. 

 Styles subulate-tipped. 

 Fruit a drupe. 



Styles thick-tipped. 

 Styles distinct. 

 Styles united. 

 Style's subulate-tipped. 



13. Janusia. 



14. Aspicarpa. 



15. Lasiocarpus. 



16. echinopterys. 



17. Henleophvtum, 



18. Spachea. 



19. Thryallis. 



20. Malpighia. 



21. Bunchosia. 



22. Byrsonima. 



1. MASCAGNIA Bertero ; Colla, Hort. Ripul. 86. 1824. 



Climbing, trailing, or partially erect shrubs. Leaves opposite ; blades membranous or 

 leathery, entire, varying from glabrous to copiously pubescent. Calyx with 8, or rarely 

 10, glands ; sepals 5, broad, sometimes as wide as long, persistent. Corolla yellow, violet, 

 blue, purplish, or lilac ; petals 5, the blades broad, entire, undulate, erose, or denticulate, or 

 rarely one of them several-lobed and with each lobe cleft into slender segments. Stamens 

 10, all anther-bearing ; filaments subulate to lanceolate ; anthers short or didymous. 

 Ovary 3-lobed. Styles 3, distinct, unequal. Samaras 3 together, with distinct or united 

 lateral wings, the dorsal wing smaller than the lateral wings, or obsolete. Embryo with 

 leafy nearly equal cotyledons. 



Type species, Mascagnia americana Bertero. 



Styles pubescent. 



Flowering peduncles 3 mm. long or more ; anthers ovoid. 1. M. macroptera. 



Flowering peduncles 1 mm. long or less ; anthers orbicular. 2. .1/. mexicana. 



Styles glabrous. 



Corolla yellow ; lateral wings of the samara distinct. 



Petals nearly alike, the blades sagittate at the base. 3. M. volubilis. 



Petals various, the blades not sagittate, that of the fifth one with forked 

 lobes. 4. M.jamaicensis. 



Corolla pink, violet, lilac, or blue ; lateral wings of the samara united at 

 the base, or at the base and the apex. 

 Androecium actinomorphic, the filaments nearly equal. 

 Samara-wings united at the base, distinct at the apex. 



Corolla over 1 cm. wide ; samara wings thick, undulate or cristate, 



the dorsal one keel-like. 

 Corolla less than 1 cm. wide; samara-wings thin, entire, the 

 dorsal one prominent. 

 Samara-wings united at the base and the apex. 

 Flowers, and fruits, borne in terminal panicles. 



Petals undulate ; glands much shorter than the sepal-body. 

 Petals denticulate ; glands nearly as long as the sepal-body. 

 Stigmas thickened ; samaras less than 2 cm. in diameter. 

 Stigmas not thickened ; samaras over 2 cm. in diameter. 

 Flowers, and fruits, not borne in terminal panicles. 



Petal-blades of an oblong type ; leaf-blades silky above. 

 Petal-blades of an orbicular type ; leaf -blades velvety above. 

 Androecium zygomorphic, the filaments very unequal. 



Leaf -blades ovate to lanceolate ; dorsal samara-wing prominent. 

 Leaf -blades obovate ; dorsal samara-wing obsolete. 



12. M. Marina. 



13. .1/. vacrintifolia. 



1. Mascagnia macroptera (Moc. & Sesse) Niedzu. Gen. 

 Masc. 27. 1908. 



Hiraea macroptera Moc. & Sesse ; DC. Prodr. 1 : 586. 1824. 

 Hiraea seplenirionalis A. Juss. Ann. Sci. Nat. II. 13: 259. 1840. 

 Hiraea Grcg%ii S. Wats. Proc. Am. Acad. 17 : 333. 1882. 

 Mascagnia septentrionalis Niedzu. in E. & P. Nat. Pfl. 3* : 55. 1890. 

 Hiraea mexicana Rose, Contr. U. S. Nat. Herb. 1 : 312. 1895. 



Branches rather pale, smooth ; leaf-blades ovate, oblong-ovate, oblong, or oblong-lan- 

 ceolate, mostly 3-8 cm. long, abruptly pointed or acute at the apex, usually with scattered 

 hairs about the midrib and veins beneath, ultimately glabrous, abruptly narrowed at the 



