116 ROSACEJE. (ROSE FAMILY.) 
Suborder II. ROSACEJE proper. 
Tribe I. SPIR^LE. The Meadow-Sweet Tribe. 
3* SPIRAEA, L. Meadow-Sweet. 
Calyx 5-cleft, persistent. Petals 5, obovate, equal. Stamens 
10 - 50. Pods (follicles) 3— 12, several- (2 — 15-) seeded. — Flow¬ 
ers white or rose-color, rarely dioecious. (Name probably from 
(nmpdco, to wind , alluding to the fitness of the plants to be formed 
into garlands.) 
§ 1. Physocarpos, Camb. — Shrubs , with simple lobed leaves and 
umbel-like corymbs: pods inflated and diverging when grown , 2-4- 
seeded. 
1. S. opullfolia, L. (Nine-Bark.) Leaves roundish, some¬ 
what 3-lobed and heart-shaped; pedicels very slender; pods 3-5, 
membranaceous. — Rocky river-banks, Maine to Wisconsin. June. 
— Shrub 4°-10° high, much branched, with white flowers, succeed¬ 
ed by membranaceous pods tinged with purple: the old bark loose 
and separating in thin layers. 
§ 2. Spiraea proper. — Shrubs , with simple leaves , the stipules obso¬ 
lete: pods (mostly 5) not inflated , several-seeded . 
2. S. corymbosa, Raf. (Flat-clustered Meadow-Sweet.) 
Nearly smooth ; leaves oval or ovate, cut-toothed towards the apex ; 
corymbs large and flat, several times compound. — Alleghanies, Penn, 
and southward. June. — Stems little branched, 1° — 2° high. Flow¬ 
ers white. 
3. S. salicifolia, L. (Willow-leaved Meadow-Sweet.) 
Nearly smooth; leaves wedge-lanceolate, simply or doubly serrate, 
floicers in a crowded panicle ; pods smooth. (S. alba, Bigel.) —Bushy 
meadows along streams: also cultivated. July.—Shrub 2°-5° high- 
flowers white or tinged with purple. 
4. S. toinentbsa, L. (Hardback. Steeple-bush.) Stems 
and lower surface of the ovate or oblong serrate leaves very woolly > 
flowers in short racemes crowded in a dense panicle; pods woolly-* 
Low grounds and meadows, commonest in New England. July. 
Shrub 3P high, the thickish leaves deep green above, and white or 
tawny beneath. Flowers rose-color. 
§ 3. UlmAria, Mcench. — Perennial herbs, with pinnate leaves and 
panided cymose flowers : pods 6-8, 1 - 2 -seeded. 
5. S. lob at a, Murr. (Queen of the Prairie.) Leaves in¬ 
terruptedly pinnate; the terminal leaflet very large, 7 - 9 -parted, the 
lobes incised and toothed ; stipules kidney-form ; panicle compound- 
