FRANGULACEAE 747 



Order 18. RHAMNALES. 



Shrubs or small trees, or commonly vines. Leaves mostly alternate. Flowers 

 regular, sometimes imperfect or incomplete. Calyx and corolla present, or the 

 latter wanting. Androecium of as many stamens as there are sepals and alter- 

 nate with them. Gynoecium a compound pistil, superior or mainly so. Fruit 

 a capsule or a berry, or drupaceous. 



Sepals manifest: petals involute : fruit capsular or drupaceous. Fam. 1. RHAMNACEAE. 



Sepals minute or obsolete : petals valvate : fruit baccate. Fam. 2. VITACEAE. 



FAMILY 1. FRANGULACEAE DC. BUCKTHORN FAMILY. 



Armed or unarmed shrubs or trees, or vines, pervaded by a bitter and as- 

 tringent principle. Leaves alternate or sometimes opposite : blades simple, 

 commonly many-nerved : stipules small, often deciduous. Inflorescence various. 

 Flowers often greenish, perfect or polygamous, or sometimes dioecious. Calyx 

 of 4-5 valvate sepals. Disk lining or filling the hypanthium, sometimes pro- 

 duced into horns. Corolla usually present, of 4-5 petals, inserted at the throat 

 of the hypanthium, or on the edge of the disk. Androecium of 4-5 stamens, 

 inserted opposite to and with the petals. Filaments distinct. Anthers versa- 

 tile, 2-celled. Gynoecium of 2-3 united carpels. Ovary 2-3-celled, partially 

 immersed in and merging into the disk. Styles and stigmas more or less united. 

 Ovules solitary, or rarely two in each cavity, anatropous, erect. Fruit capsular 

 or drupaceous, rarely winged, commonly separating into several nutlets. Seeds 

 with a smooth or furrowed fibrous membranous crustaceous or horny testa. 

 Endosperm wanting or fleshy. Embryo with often broad cotyledons. [Rham- 

 naceae Dumort.] 



Fruit pulpy, with a 1-3-celled stone. 

 Petals wanting. 



Sepals crested. 1. RHAMNIDIUM. 



Sepals not crested. 



Endosperm ruminated. 2. REYNOSIA. 



Endosperm not ruminated. 3. CONDALIA. 



Petals present. 



Petals hooded and clawed, obtuse. 



Flowers clustered : styles nearly distinct : ovule solitary. 4. ZIZYPHUS. 



Flowers racemed : style united : ovules 2 in each cavity. 5. KARWINSKIA. 



Petals not hooded, sessile, acute. 6. BERCHEMIA. 



Fruit dry or berry-like, with 2-4 separating nutlets. 

 Fruit pulpy. 



Hypanthium flattish : disk conspicuous. 7. SAGERETIA. 



Hypanthium cup-like : disk inconspicuous, lining the hypanthium. 8. RHAMNUS. 



Fruit dry. 



Fruit not winged, seated in the persistent calyx. 



Sepals inflexed : petals on slender claws. 9. CEANOTHUS. 



Sepals spreading : petals sessile, involutely folded over the filaments. 10. COLUBRJNA. 



Fruit winged, crowned with the sepals. 11. GOUANIA. 



1. RHAMNIDIUM Keiss. 



Shrubs or small trees, with unarmed branches. Leaves nearly opposite : blades firm, 

 entire, pinnately nerved : stipule* minute. Flowers perfect, in short-peduncled axillary 

 cymes. Sepals 5, crested, longer than the hypanthium. Petals wanting. Stamens 5 : 

 filaments longer than the anthers. Ovary 2-celled : styles united, merely notched or 2-3- 

 lobed. Ovule solitary. Drupe with an incompletely 2-celled stone. Seed with a large 

 embryo. Endosperm not ruminated. 



1. Rhamnidium f^rreum (Vahl) Sarg. A shrub or small tree, reaching a height of 

 9 m. , with a trunk diameter of 25 cm. , its bark broken into rounded ridges. Leaf-blades thin 

 but leathery, ovate or oval, 3-6 cm. long, usually notched and mucronulate at the apex, 

 entire or undulate, abruptly narrowed or rounded at the base, becoming glabrous ; petioles 

 3-6 mm. long, pubescent especially on the upper side : flowers inconspicuous, 3-5 in axil- 

 lary cymes : calyx 4-5 mm. broad, glabrous : sepals 5, ovate, acute, prominently crested on 

 the inner side : stamens 5, erect: drupes subglobose or oval, 5-8 mm. long, black. \_Con- 

 dalia ferrea (Vahl) Griseb. ] 



Along the coast, Florida and the Keys. Also in the West Indies. Spring. BLACK IRONWOOD. 



