410 lI.MACK.i:. (kLM lAMILY.) 



Oki>i:k \-2'>. I'LMACEyE. (Ki.m 1'a.mjlv.) 



Trees, witli wateiT juice, aheruatu umlividtd stipulate leaves, and per- 

 fect or jKilygamous apetalous ilowers. — Calyx 4 - !J-lobed. Stamens 4-9, 

 inserted on the base of the cahx, erect in the bud. Ovary 1 - 2-eelled. 

 Ovules solitary, suspended. Styles 2, spreading. Fruit nienibranat eous 

 or dnipaeeous. Embryo straight or curved, without albunieu. Cotyle- 

 dons leafy. 



Synopsis. 



♦ Fruit dry. Anthers oxtrorse. 



1. ULMU5. Flowers perfect. Ovary 2-cellcd. Fruit winged. 



2. PLANKKA. Flowers polygamous. Ovary 1-celled. F'ruit wingless. 



• * Fruit a drupe. Anthers introrse. 

 8. CKLTIS. Flowers polygamous. Ovary 1-celled. Cotyledons curved. 



1. ULMUS, L. Elm. 



Flowers perfect. Calyx bell-shaped, 4 - 9-cleft. Stamens 4-9, slender, ex- 

 serted : anthers extrorse. Ovary 2-celled. Styles short. Fruit 1-celled, 1 -seeded, 

 surrounded by a broad mcmbranaeeous wing. Embryo straight. — Trees. 

 Leaves short-petioled, mostly oblique, doubly serrate, straight-veined. Stipules 

 deciduous. Flowers grcenisli or purplish, clustered, appearing before the leaves. 



1. U. fulva, Michx. (Slippery Elm.) Branchlets pubescent; leaves 

 thick, ovate-oblong, acuminate, broadly serrate, slightly ol)lique at the base, very 

 rough above, pubeseent beneath ; calyx and short pedicels pubescent ; fruit 

 orbicular, pul)eseent on the sides, smooth on the marjiins, with the obtuse teeth 

 erect ; expanding buds rusty-tomentose. — Ilich woods, West Florida, and north- 

 ward. Feb. and March. — A small tree. Leaves 4' -8' long. Fruit 8" -9" 

 wide. Inner bark very mucilaginous. 



2. U. Floridana, n. sp. Branchlets smooth; leaves thick, oblong-ovate, 

 acute or slightly acuminate, broadly serrate, oblique at the base, smooth above, 

 more or less pubescent beneath ; pedicels very slender, somewhat racemose, and, 

 like the calyx, smooth ; fruit orbicular, fringed on the margins, with the short 

 and broad teeth erect. — Banks of the Chipola River, at Marianna, West Florida. 

 Feb. and March. — A tree 30° -40° high, with brittle branches. Leaves 3'- 4' 

 long. Fruit 2" -3" in diameter. Bud-scales downy on the margins. 



3. U. Amei'icana, L. (Elm.) Branchlets and buds smooth; leaves 

 thin, obovatc-oblong, or oval, oblique at th6 base, sharply serrate, abruptly acu- 

 minate, smooth above, pubeseent, or at length smooth beneath ; pedicels clustered, 

 slender, smooth, like the calyx ; fruit oval or oliovate, downy on the margins, 

 witli tlie sharp teeth connivent. — Low grounds, Florida, and northward. Feb. 

 and March. — A large tree, with spreading branches. Leaves 2' -4' long. 

 Fruit 6" long. 



Var. ? aspera. Leaves larger (3' -6') on shorter petioles, oval-oblong, acu- 

 minate, very oblique or half-cordate at the base, very rough above, pubeseent 



