456 KOSACKAK (RUSK FAMILY) 



1. PHYSOCARPUS Maxim. NINE-BARK 



Carpels 1-5, inflated, 2-valvecl ; ovules 24. Seeds roundish, \\ith a smooth 

 and shining crustaceous testa and copious albumen. Stamens 30-40. Other- 

 wise as Spiraea. Shrubs, with simple palmately lobed leaves and umbel-like 

 corymbs of white flowers. (Name from 000-a, a pair of bellows, and Kap?r6s, 

 fruit.) 



1. P. opulifblius (L.) Maxim. Shrub, 1-3 in. high, with long branches, the 

 old bark loose and separating in numerous thin layers ; leaves roundish, some- 

 what 3-lobed and heart-shaped ; the purplish membranaceous pods usually 3, 

 essentially glabrate, very conspicuous. (Spiraea L. ; Opulaatcr Kt/.e.) Rocky 

 banks of streams, Que. and N. E. to Fla., w. to 111. Often cultivated. 



Var. intermSdius (Rydb.) Robinson. Pods permanently pubescent. (Opu- 

 laster intermedius Rydb.) Similar situations, s. Mich, to S. Dak., Ark., and 

 Ala. 



2. SPIRAEA [Tourn.] L. 



Calyx 6-cleft, short, persistent. Petals 5, obovate, equal, imbricated in the 

 bud. Stamens 10-50. Pods (follicles) 5-8, not inflated, few-several-seeded. 

 Seeds linear, with a thin or loose coat and no albumen. Shrubs, with simple 

 leaves, and white or rose-colored flowers in corymbs or panicles. (The Greek 

 name, from aireipav, to twist, from the twisting of the pods in some of the 

 original species.) 



Flowers in compound corymbs. 



Calyx-tube top-shaped, pubescent 1. S.japonica. 



Calyx-tube bell-shaped, smoothish. 



Leaves 2.5-5 cm. broad 2. 8. corymbotta. 



Leaves 1-1.6 cm. broad 3. 8. virginiana, 



Flowers racemosely or spicately panicled. 

 Leaves smoothish, scarcely paler beneath. 



Pedicels fascicled, I. 1 ) cm. long; flowers usually double . . . .4. 

 Flowers densely raccmo-paniculate ; pedicels 2-6 mm. long. 



Inflorescence toim-ntulose . r >. 



Inflorescence subglabrous or sparingly villous (i. >'. 



Leaves green above, densely tomentose and white or tawny beneath . . 7. S. tomentosa. 



1. S. JAPONIC v L. f. Stems 1 m. or more high ; leaves 7-9 cm. long, glau- 

 cous beneath; petals pink to deep rose-color. Frequent in cultivation, and 

 occasionally escaping, s. Ct. (Graves) and e. Pa. (Introd. from Asia.) 



2. S. corymbbsa Raf. Stems erect, dark purple, simple or nearly so ; leaves 

 oval or broadly oblong, smoothish, of firm, texture, toothed from near the middle 

 to the rounded or obtuse apex, 2.5-5 cm. broad ; flowers white; corymbs 4-10 

 cm. broad. (S. betulifolia, var. Wats.) In the Allegheny Mts., N. J. (accord- 

 ing to Britton) to W. Va. and Ga. 



3. S. virginiana Britton. Glabrous, much-branched ; leaves lance-oblong, 

 1-1.6 cm. broad, often acute or acutish at the base ; flowers white, about (5 mm. 

 broad ; pedicels and calyx glaucous. On rocks, W. Va. (Millspaugh) to N. C. 

 and Tenn. Not seen ; description compiled. 



4. S. I'Ki-NiKohiA Sieb. & Zucc. Finely pubescent; leaves ovate-oblong, 

 obtuse, cuneate at the base, serrulate ; flowers white, often double, 1 cm. in 

 diameter. Persisting after cultivation, and tending to escape to roadsides, e. 

 Mass, and Ct. (Introd. from Japan.) 



5. S. salicifblia L. (Mi. VPOW-SWKKT.) Erect shrub, 3-V2 dm. high, with 

 tough yel/nii-is/i-}>ri>irn stems,' leaves finely serrate, lance-oblong, 5-7 em. long, 

 1-1.8 cm. broad, rather linn' in texture ; inflorescence thyrs>jd, toinentulosr ; 

 flowers 6-8 mm. in diameter; petals sub<.rl>irular. white. Chiefly in low 

 ground, N. V. to X. C., Mo., and northwest w. ('Asia.) 



6. S. Iatif61ia Borkh. (MKAKOW-SWKKT.) ,S7r?/<s )/<! or purplish-brown f 

 leaves thin, more rom-xi /// x.-ri-utt . mostly l.:>-4cm. broad ; inflorescence smooth- 



: pish; petals white or pink. The common Meadow-sweet in e. N. A.; in rocky 

 pastures, etc.. N't'd. to Va. 



S- tomentdsa I>. ( HAUIHI \< K. Suini. lii -n. 8ten* .//// Ivuxsr sw- 

 s c 



