RHAMNACE^. (BUCKTHORN FAMILY.) 73 



2. BERCHEMIA, Neck. Sdpple-Jack. 



Calyx 5-cleft, the tube hemispherical. Petals 5, sessile, concave, as long as 

 the calyx. Ovary free, 2-ceiled, half immersed in the fleshy disk. Styles united. 

 Stigmas 2. Drupe oblong, 2-celled, 2-seeded. — Erect or twining shrubs, with 

 alternate pinnately-veined leaves, with minute stipules, and small greenish axil- 

 lary or panicled flowers. 



1. B. VOlubilis, DC Stem twining; leaves oblong, acute, wavy on the 

 margins, glossy above, tlie simple veins oblique ; flowers in small terminal pan- 

 icles ; drupe purple. (Zizyphus volubilis, Willd.) — Swamps, Florida to North 

 Carolina, and westward. June. 



3. SAGERETIA, Brongn. 

 Calyx 5-cleft, the tube hemispherical, the lobes carinate within. Petals obo- 

 vatc, shorter than the calyx, concave. Ovary free, 3-celled. Stigmas 3, nearly 

 sessile. Drupe baccate, composed of three even 1-seeded indehiscent nutlets. 

 Seeds not grooved. Cotyledons flat. — Slender trailing shrubs, with opposite 

 branches and leaves, and minute whitish spiked flowers. 



1. S. Michauxii, Brongn. Stem vine-like (6° -18° long), with spine- 

 like spreading branches ; leaves (1' long) nearly sessile, ovate or oblong-ovate, 

 acute, finely serrate, smooth and shining, persistent ; spikes slender, interrupted, 

 mostly panicled ; petals minute ; drupe dark-purple, globose. (Rhamnus minu- 

 tiflorus, jl//c/u-.) — Dry sandy soil along the coast, Florida to North Carolina. 

 September. — Drupes pleasantly acid. 



4. RHAMNUS, Tourn. Buckthorn. 



Calyx 4 - 5-clcft, the tube urceolate, lined with a thin disk. Petals small, ob- 

 ovate, concave, often wanting. Ovary free, 2-4-celled. Styles united below. 

 Stigmas 2-4. Drupe baccate, composed of 2-4 somewhat dehiscent nutlets. 

 Seeds grooved on the back. Raphe dorsal. Cotyledons leafy, revolute. — 

 Shrubs, with alternate stipulate finely veined leaves, and small axillary clustered 

 polygamous or dioecious greenish flowers. 



1. R. laneeolatUS, Pursh. Leaves oblong-lanceolate, acute, or those of the 

 flowering branches oblong and obtuse, serrulate ; flowers clustered, on short pedi- 

 cels, with long styles, or the more fruitful ones scattered on longer pedicels, and 

 with short styles ; petals emarginate ; drupe 2-seeded. — Hills and river-banks, 

 in the upper districts, Alabama and northward. June. — A tall shrub. Drupes 

 black, as large as a grain of pepper. 



5. FRANGULA, Toum. 



Seeds not grooved. Raphe lateral. — Leaves strongly parallel-veined. Flow- 

 ers perfect. Otherwise as in Rhamnus. 



1. F. Caroliniana, Gray. (Carolina Bockthorn.) Leaves oblong, 

 wavy and finely sen-ulate on the margins, the slender petioles and many-flowered 

 short-stalked umbels pubescent ; petals 5, minute ; stigmas 3 ; drupe globose, 



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