Zizyphus. RHAMNACE^E. 99 



1. P. Myrsinites, Eaf. Much branched, a foot or two high, leafy : leaves 

 ovate to oblong or oblanceolate, J to 1^ inches long, cuneate at base, serrate or ser- 

 rulate, obtuse or acutish : flowers a line in diameter, on pedicels a line or two long : 

 fruit 2 lines long, smooth. Ilex (]) Myrsinites, Pursh. Myginda myrtifolia, Nutt. ; 

 Hook. Fl. i. 120, t. 41. Oreophila myrtifolia, Xutt. ; Torr. & Gray, Fl. i. 259. 



Hillsides on the South Yuba (Bigelow) ; Mt. Shasta, at 4,000 to 5,000 feet (Brewer) ; north- 

 ward in the mountains to British Columbia, and in the Rocky Mountains ranging south to New 

 Mexico. 



ORDER XXVII. RHAMNACE^J. 



Shrubs or small trees, with simple undivided leaves, small and often caducous 

 stipules, and small regular flowers ; well distinguished from the related orders by 

 the valvate aestivation of the calyx, and the perigynous stamens as many as its lobes 

 and alternate with them ; the ovules solitary (rarely in pairs) and erect in the 2 to 

 4 cells of the ovary. Flowers sometimes polygamo-dioecious, often apetalous. A 

 conspicuous disk adnate to or lining the short tube of the calyx. Petals often 

 unguiculate, mostly involute each around a stamen in the bud. Ovary either free 

 or adnate by the disk to the tube or base of the calyx : style or stigma 2 - 4-lobed. 

 Seeds solitary in the cells, anatropous, with a large straight embryo in sparing 

 fleshy albumen : cotyledons flat or plano-convex : radicle short. 



A widely distributed order, of between 30 and 40 genera and four or five hundred species, of 

 which Ceanothus is the only extensive North American genus. The herbage has some bitterness 

 and astringency, and the fruit when fleshy or juicy is commonly mawkish or nauseous, but edible 

 in Zizyphus, one species of which furnishes the basis of Jujube paste. 



* Fruit with a single 1 - 3-celled hard stone. 



1. Zizyphus. Cells 1-ovuled. Leaves alternate, not punctate. Spiny shrubs. 



2. Karwinksia. Cells 2-ovuled. Leaves opposite, pellucid-punctate. Unarmed. 



* * Fruit berry-like or dry, containing 2 to 4 separating seed-like nutlets. 



3. Rhamnus. Calyx and disk free from the ovary; calyx-lobes erect or spreading. Petals 



small, short-clawed, or none. Filaments very short. Fruit berry-like, with 2 to 4 mostly 

 indehiscent nutlets. Leaves alternate. 



4. Adolphia. Disk covering the calyx-tube, free from the ovary ; calyx-lobes spreading. 



Petals short-spatulate, hooded. Fruit dry, with 3 dehiscent nutlets. Spinose : leaves 

 opposite and very small, or none. 



5. Ceanothus. Calyx and disk adnate to the base of the ovary ; calyx-lobes connivent. Petals 



long-clawed, hooded. Filaments exserted. Fruit dry, with 3 dehiscent nutlets. 



1. ZIZYPHUS, Juss. 



Calyx 5-cleft, with acute spreading lobes ; the disk filling the broadly turbinate 

 tube. Petals 5, hooded, deflexed. Ovary connate with the disk at base, 2-celled or 

 rarely 3-4-celled; cells 1-ovuled: styles 2 to 4, free or united. Drupe fleshy, 

 with a woody 2 - 3-celled nut. Spiny shrubs or trees ; with thick alternate leaves, 

 mostly 3 - 5-nerved ; stipules small and deciduous or spinulescent ; flowers small, 

 greenish, in axillary cymes ; fruit often edible. 



About 50 species, chiefly of Egypt and Southern Asia. Three species are found in the region 

 between the Gulf of Mexico and the Pacific, with the habit rather of the American genus Con- 

 dalia, and with characters which tend to the union of the two genera. Another scarcely distinct 

 genus is Microrhamnus, Gray (referred to Condalia by Baillon), of a single species, inhabiting 

 Arizona and New Mexico. 



1. Z. Parryi, Torrey. Much branched, 4 to 15 feet high, glabrous; the smooth 

 flexuous branches armed with straight leafy spines : leaves obovate, obtuse or retuse, 



