FKANGULACEAE 749 



1. Zizyphus obtusifolia (Hook.) A. Gray. A rigid spinescent much-branched 

 pubescent or glabrous shrub. Leaf -blades ovate or oblong-ovate, or rarely narrowly oblong, 

 1-3 cm. long, acutish varying to retuse, entire or shallowly crenate, more or less abruptly 

 narrowed at the base, glabrous or nearly so, a little paler beneath than above ; petioles 

 mainly - as long as the blades : clusters rarely surpassing the petioles : peduncles and 

 pedicels 1-2 mm. long, villous-pilose : calyx pubescent like the pedicels, about 3 mm. 

 broad : sepals triangular, acute : petals 5, shorter than the sepals, longer than the 5 stamens : 

 drupe subglobose, 8-10 mm. long, black. 



On plains and prairies, Texas to Arizona. Spring. LOTIBUSH. TEXAS BUCKTHORN. 



5. KARWINSKIA Zucc. 



Shrubs or small trees. Leaves opposite or nearly so : blades entire, prominently 

 nerved : stipules deciduous. Flowers perfect, few together in axillary cymes. Hypanthium 

 turbinate or hemispheric. Sepals 5, triangular, keeled within. Petals 5, hooded, clawed. 

 Stamens 5, inserted with the petals under the edge of the disk which clothes the hypanthium: 

 filaments subulate, surpassing the petals. Ovary immersed in the disk, 2-3-celled : styles 

 united almost to the apex : stigmas obtuse. Ovules 2 in each cavity. Drupe varying from 

 ovoid to subglobose, tipped with the persistent base of the style, the stone 1-2-celled. Seeds 

 erect. Testa membranous, dark-veined. Endosperm thin. 



1. Karwinskia Humboldtiana Zucc. A shrub or small tree, reaching a height of 

 7m., the twigs and young leaves sometimes puberulent. Leaf -blades firm, oblong, oval, 

 oblong-ovate or oblong-lanceolate, 3-9 cm. long, rounded or acute at the apex, entire, 

 more or less revolute, abruptly rounded or narrowed at the base, the lateral nerves promi- 

 nent ; petioles slender, 5-15 mm. long : cymes about 1 cm. long : calyx glabrous, 2.5-3 mm. 

 broad ; sepals triangular, about as long as the hypanthium, acute : drupes subglobose or 

 oval, 10-12 mm. long, apiculate by the persistent style, brownish black. 



On dry plains or prairies, Texas to Lower California and Central America. 



6. BERCHEMIA Neck. 



Erect or high-climbing shrubs. Leaves alternate : blades leathery, with ascending 

 nerves straight and parallel : stipules small, deciduous. Flowers perfect or polygamous, 

 axillary, or sometimes in terminal panicles. Hypanthium hemispheric or turbinate. 

 Sepals 5. Disk clothing the hypanthium, its margin free. Petals 5, sessile, hooded. 

 Stamens 5 : filaments filiform. Ovary half-immersed in the disk, but free, 2-celled : styles 

 short, united : stigmas 2. Ovules 2 in each cavity. Drupe somewhat flattened, with a 

 leathery sarcocarp, and a 2-celled crustaceous or woody stone. Seeds with a membranous 

 testa. Endosperm wanting. 



1. Berchemia scandens (Hill) Trelease. A glabrous twining or climbing shrub. 

 Stems much branched, 2-30 m. long, the branches spreading at right angles : leaf-blades 

 firm, oval, elliptic, oblong, sometimes varying to lanceolate, 4-8 cm. long, entire or undu- 

 late-crenate, abruptly narrowed or rounded at the base, the lateral nerves prominent ; petioles 

 slender, 0.5-1 cm. long: panicles 1.5-5 cm. long, terminal: calyx glabrous; sepals 5, 

 triangular or ovate-triangular, longer than the hypanthium, acute or short-acumim te : 

 petals 5, obovate, acute, about as long as the sepals, sessile, the edges more or less invo- 

 lute : drupes oblong or ovoid-oblong, 6-8 mm. long. [B. volubilis DC.] 



In damp soil, Virginia to Missouri, Florida and Texas. Spring. 



7. SAGERETIA Brongn. 



Armed or unarmed weak shrubs, with opposite or nearly opposite branchlets. Leaves 

 opposite or nearly so : blades reticulated : stipules minute, deciduous. Flowers perfect, in 

 axillary clusters or terminal panicled spikes. Sepals 5, keeled within. Disk cup-like, 

 clothing the hypanthium, margin free, 5-lobed. Petals 5, clawed, hooded. Stamens 5 : 

 filaments distinct. Ovary immersed in the disk, free, 3-celled : style 3-grooved : stigmas 3. 

 Drupe berry-like, separating into 3 leathery nutlets. Seeds elongated, not grooved. En- 

 dosperm thin. 



1 Sageretia minutiflora (Michx. ) Trelease. A trailing or straggling spinescent 

 shrub, with tomentose twigs and young leaves, and diverging branches. Leaf-blades 

 leathery, ovate or orbicular-ovate, 1-5 cm. long, acute or short-acuminate or rarely sub- 

 mucronate, serrulate, shining above, rounded or subcordate at the base, short-petioled : 



