BUCKTHORN FAMILY. 105 



Calyx free from the ovary. 



1. BERCHEMIA. Twining climbers, with alternate, straight-veined leaves. Petals 5, 



without claws, rather longer than the stamens. Disk thick, nearly filling the bottom 

 of the calyx. Ovary 2-celled, becoming a 2-celled, small stone-fruit. 



2. 8AGERETIA. Trailing shrubs, with opposite, persistent leaves. Petals 5, minute. 



Ovary 3-celled, becoming a 3-seeded stone-fruit. 



3. KHAMNUS. Erect shrubs or trees. Petals 4 or 5 or 0, notched, with short claws. 



Stamens short. Ovary 2-4-celled, becoming a black, berry-like fruit, containing 2-4 

 cartilaginous seed-like nutlets. Flowers greenish, axillary, mostly in small clusters, 

 in early summer. Berry -like fruit mawkish. 



* * Calyx loith the disk coherent with the base of the ovary and fruit. 



4. CEANOTHUS. Erect or depressed shrubs or undershrubs. Petals 5, hood-shaped, 



spreading, their claws and the filaments slender. Ovary 3-celled, when ripe becom- 

 ing a cartilaginous or crustaceous 3-seeded pod. Flowers in little umbels or fascicles, 

 usually clustered in dense bunches or panicles, handsome, the calyx and even the 

 pedicels colored like the petals and stamens. Ours are low undershrubs, with white 

 flowers. 



1. BERCHEMIA, SUPPLEJACK. (Probably named for some 



person.) 



B. volubilis, DC. Climbing on high trees, smooth, with very tough and 

 lithe stems (whence the popular name) ; leaves small, oblong-ovate and 

 simply parallel-veined ; flowers greenish white, in small panicles termin- 

 ating the branchlets, in early summer ; drupe purple. Common in low 



grounds S. 



2. SAGERETIA. (Named for Sageret, an able French agriculturist.) 



S. Michauxii, Brongn. Stems vine-like and many feet long, trailing 

 in the sands along the coast from N. C., South ; leaves an inch long and 

 nearly sessile, finely serrate, shining ; spikes of flowers slender and inter- 

 rupted, clustered ; drupe dark purple. 



3. RHAMNUS. BUCKTHORN. (The ancient name.) 



* Plotters usually dioecious ; nutlets and seeds deeply grooved on the back; 



winter buds scaly. 



t- Flowers with petals, the parts in fours; leaves minutely serrate. 



R. cathdrtica, Linn. COMMON BUCKTHORN. Cult, from Eu., for 

 hedges, run wild in a few places ; forms a small tree, with thorny branch- 

 lets, ovate or oblong leaves, and 3-4-seeded fruit. 



R. lanceolate, Pursh. NARROW-LEAVED B. Wild from Penn. S. and 

 W. ; shrub not thorny, with lanceolate or oblong leaves and 2-seeded fruit. 



-H- H- Flowers without petals ; stamens and lobes of the calyx 5. 



R. alnif61ia, L'Her. ALDER-LEAVED B. Wild in cold swamps N. ; a 

 low shrub, with oval, acute, serrate leaves, and 3-seeded, berry -like fruit. 



* * Floicers perfect; nutlets and seeds not furrowed; winter buds naked. 



R. Caroliniana, Walt. INDIAN CHERRY. A thornless shrub or low 

 tree, with oblong and almost entire, rather large leaves ; flowers solitary 

 or in small clusters in the axils, in early summer on peduncles shorter 

 than the petioles ; the 3-seeded fruit at first crimson, finally black. Wild 

 in wet grounds, from N. .1. and Ky. S. 



R. Purshiana, DC. From the N. W. coast, with peduncles much 

 longer than the petioles of the serrulate leaves, and R. Frdngula, Linn., 

 from Eu., with the flower clusters sessile and leaves entire, are occasion- 

 ally planted. 



