ACERACEAE. 159 



Family 52. CELASTRACEAE. STAFFTREE FAMILY. 



Shrubs, often climbing; leaves simple and undivided, alternate 

 or opposite; stipules none or small and early withering; flowers 

 regular, usually perfect, small; pedicels commonly jointed; 

 calyx 4-5-lobed, the lobes imbricated; petals 4-5, spreading; 

 stamens 4-5, perigynous on a disk, alternate with the petals; 

 ovary sessile, free from or confluent with the disk; fruit a some- 

 what fleshy dehiscent pod ; endosperm fleshy. 



Evergreen smooth shrub; stamens 4; petals 4. 222. PACHISTIMA, 159. 



Deciduous spiny shrub; stamens 10; petals 5. 223. FORSELLESIA, 159. 



222. PACHISTIMA. 



Low evergreen shrubs; leaves opposite, smooth, serrulate, cori- 

 aceous; flowers perfect, very small, green, solitary or fascicled 

 in the axils; calyx-lobes 4, broad; petals 4; stamens 4, on the 

 edge of the disk; style very short; ovary free; pod small, oblong, 

 2-celled; seeds 1 or 2, enclosed in a white membranous many- 

 cleft aril. 



Pachistima myrsinites (Pursh) Raf. Evergreen glabrous shrub, much 

 branched, 30-60 cm. high; leaves oblong, lanceolate or obovate, acute or obtuse, 

 cuneate at base, serrulate, nearly sessile, 1-3 cm. long, the margin somewhat 

 revolute; flowers yellowish or purplish, 3 mm. broad; peduncles and pedicels 

 short, 2-3 mm. long; capsule oblong, acute, 5-6 mm. long. In woods, Thatuna 

 Hills. 



223. FORSELLESIA. 



Low and rigid shrubs, with slender spinescent branches ; leaves 

 small, alternate, sessile, entire; stipules minute, setaceous-subu- 

 late; flowers small, perfect, solitary, terminating short axillary 

 branches or in spur-like fascicles ; calyx deeply 5-cleft ; petals 5 ; 

 stamens 10; style short or none; ovary 1 -celled, of a single ovoid 

 carpel; ovules 2; fruit a coriaceous follicle, 1-2-seeded. 



Forsellesia spinescens (Gray) Greene. Low much branched shrubs, 

 somewhat spiny, 1 m. or less high; leaves numerous, oblanceolate, acute, 

 short-petioled, glabrous or puberulent, pale-green and glaucous, 6-16 mm. 

 long; stipules minute, usually reddish; flowers on pedicels as long as the leaves; 

 petals yellow, narrow, 6 mm. long; capsules ovoid, acutely beaked, striate, 

 often curved. In basalt crevices, along Snake River. 



Family 53. ACERACEAE. MAPLE FAMILY. 



Trees or shrubs ; leaves simple or pinnately or palmately com- 

 pound, opposite, without stipules (in ours) ; flowers small, regular 

 (in ours), polygamous or dioecious; sepals 4-5; petals often none 

 (in ours); stamens 3-12, inserted on the fleshy disk; ovary 2- 



