RHAMNACE2E. (BUCKTHORN FAMILY.) 35 



etipe, 2-celled; style short; fruit a broadly winged orbicular samara, 2-seeded. Flowers 

 email, greenish-white, in terminal cymes or compound corymbs. 



1. P. angustifolia, Benth. A shrub 5 to 25 ft. high, with chestnut colored punc- 

 tate bark; leaves 3-foliolate. 



ORDER 17. CELASTRACE.ZE. 



Sufficiently characterized by the genus 



1. EUONYMTJS, Tourn. 



Sepals and petals 4 or 5, widely spreading; Stamens as many very short on an angled 

 disk; ovary immersed in the disk, 3-5-valved, colored, often warty. Fruit a red aril. 

 Shrubs, with 4-angled branches, opposite petioled exstipulate serrate smooth leaves, and 

 flowers in loose cymes on axillary peduncles. 



1. B. occidentalis, Nutt. 7 to 15 ft. high; leaves ovate to oblong-lanceolate, 

 acuminate, serrulate, 2 to 4 inches long; peduncles 1-4-flowered; flowers dark reddish- 

 brown, 4 to 6 lines in diameter, the parts in fives. 



ORDER 18. RHAMNACE-ffi. 



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

 and small regular flowers, the stamens borne on the calyx and alternate with its lobes; 

 ovary 2 to 4-celled. Flowers often apetalous; a conspicuous disk adiiate to the short tube 

 of the calyx; petals often clawed; style or stigma 2-4-lobed; fruit berry-like or dry, con- 

 taining 2 to 4 seed-like nutlets. 



Calyx and disk free from the ovary; filaments short; fruit berry -like Rhamnus, 1 



Calyx and disk adherent to the ovary; filaments long; fruit dry Ceanothus. 2 



1. RHAMNUS, L. 



Small greenish flowers; calyx 4-5-cleft, with erect or spreading lobes, the campanulate 

 tube persistent; petals 4 or 5 or none, on the margin of the disk; claws short; stamens 4 

 or 5; leaves evergreen. 



1. Flowers dioecious, apetalous, solitary or fascicled in the axils. 



1. R. crocea, Nutt. Much branched, 3 to 15 ft. high; leaves coriaceous, oblong 

 or obovate to obicular, 3 to 18 lines long, acutely denticulate, usually yellowish brown or 

 copper-colored beneath; fruit red. 



2. Flowers mostly perfect in pedunculate cymes. 



2. R. Californica, Esch. Spreading 4 to 18 ft. high; leaves ovate-oblong to ellip- 



