ULMACE^E. (ELM FAMILY.) 439 



ORDER 125. ULMACE^E. (ELM FAMILY.) 



Trees, with watery juice, alternate undivided stipulate leaves, and 

 perfect or polygamous apetalous flowers. Calyx 4 - 9-lobed. Sta- 

 mens 4-9, inserted on the base of the calyx, erect in the bud. Ovary 

 1 -2-celled. Ovules solitary, suspended. Styles 2, spreading. Fruit 

 membranaceous or drupaceous. Embryo straight or curved, without 

 albumen. Cotyledons leafy. 



Synopsis. 



* Frui dry. Anthers extrorse. 



1. ULMUS. Flowers perfect. Ovary 2-celled. Fruit winged. 



2. PLANERA. Flowers polygamous. Ovary 1-celled. Fruit wingless. 



* * Fruit a drupe. Anthers iutrorse. 



3. CELTIS. Flowers polygamous. Ovary 1-celled. Cotyledons wrinkled. 



4. TREMA. Flowers polygamous. Cotyledons incurved. Albumen fleshy. 



1. ULMUS, L. ELM. 



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

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

 seeded, surrounded by a broad membranaceous wing. Embryo straight. 

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

 Stipules deciduous. Flowers greenish or purplish, clustered, appearing be- 

 fore the leaves. 



1. U. fulva, Michx. (SLIPPERY ELM.) Branchlets pubescent ; leaves 

 thick, ovate-oblong, acuminate, broadly serrate, slightly oblique at the base, 

 very rough above, pubescent beneath ; calyx and short pedicels pubescent ; 

 fruit orbicular, pubescent on the sides, smooth on the margins, with the 

 obtuse teeth erect ; expanding buds rusty-tomentose. Rich woods, West 

 Florida, and northward. Feb. -March. A small tree. Leaves 4' -8' long. 

 Fruit 8" - 9" wide. Inner bark very mucilaginous. 



2. U. Floridana, Chapm. 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 race- 

 mose, and, like the calyx, smooth ; fruit orbicular, fringed on the margins, 

 with the short and broad teeth erect. Banks of the Chipola River, at Mari- 

 auna, West Florida. Feb. -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- Americana, L. (ELM.) Branchlets and buds smooth ; leaves 

 thin, obovate-oblong, or oval, oblique at the base, sharply serrate, abruptly 

 acuminate, smooth above, pubescent, or at length smooth beneath ; pedicels 

 clustered, slender, smooth, like the calyx ; fruit oval or obovate, downy on 

 the margins, with the sharp teeth connivent. Low grounds, Florida, and 

 northward. Feb. - March. A large tree with spreading branches. Leaves 

 2' - 4' long. Fruit 6" long. 



