188 SAXIFRAGACER. aucun: 
20 ARUNOUS L. 
Herbaceous perennials with repeatedly ternately divided leaves 
without stipules and loose panicles of small white flowers termi- 
nating the branches.. Flowers dia-cious. Calyx 5-cleft, marces- 
cent in fruit; disk entire, coherent to the tube. Petals 5. 
Stamens numerous, hypogynous. Carpels 3-5, distinct, sessile, 
becoming cartilagineus several-seeded follicles. Seeds with a 
loose membranaceous testa and no albumen. 
A. vulgaris Raf. Syly. Tell. 152. Spirea Aruncus L. Glabrous: 
stems stout, 2-6 feet high or more, branching: leaves large, ternately 
decompound; leaflets thin, sparingly villous beneath, ovate to lanceolate, 
acuminate, 2-5 inches long sharply and laciniately doubly toothed, the 
terminal ones broadest: panicles large, compound, pubescent; flowers a 
line broad, nearly sessile; petals spatulate; filaments twice as long as the 
petals; styles short; carpels 3-5, several seeded, globose, the pedicels 
reflexed infruit. Along streams in mountainous districts, Alaska to Cali- 
fornia and across the Continent. 
OrpER XXX SAXIFRAGACEE Dumort. Anal. Fam. 36. - 
Herbs with bland watery often astringent juice, alternate or 
opposite leaves without true stipules and mostly perfect 
flowers. Sepals 4-5, united or nearly distinct, imbricate in the 
bud. Petals as many as sepals and alternate with them, rarely 
wanting. Stamens as many or twice as many as petals, rarely 
fewer, inserted into the throat of the calyx; anthers introrse. 
Ovary either free from the calyx or coherent with its tube, 1-3- 
celled with parietal placentz: ovules mostly numerous: styles 
distinct or more or less united. Fruit capsular, usually beaked 
with the distinct summits of the carpels, opening along the inner 
suture of each, septicidal. Seeds anatropous, usually small and 
numerous. Embryo straight, in the axis of fleshy albumen: 
radical cylindrical: cotyledons short. 
*Ovary with 2 or rarely more cells and placentee in the axis, or of as 
many distinct carpels: fruit capsular or follicular. 
1. Leptarrhena. Petals 5; stamens 5: carpels 2, distinct, free and ex- 
serted from the small calyx. 
2. Peltiphyllum. Petals deciduous: stamens 10, inserted at the union 
of the ovary and calyx-tube: carpels distinct, adnate to the tube of 
the calyx: leaves peltate, radiately veined. 
3. Saxifraga. Petals deciduous: stamens 10, rarely more, inserted 
under the ovary: carpels 2, rarely 3, more or less united at base, free 
from or adnate to the base of the calyx. 
4, Saxifragopsis. Petals persistent, soon deflexed: stamens 10, insert- 
ed at the base of the calyx: carpels united at base, adnate to the lower 
part of the calyx-tube: leaves palmately veined, the blade obscurely 
articulated to the petiole. ; 
5. Sullivantia. Petals persistent: stamens 5. inserted on the throat 
of the calyx: carpels united at base, adnate to the tube of the calyx. 
6. Boykinia. Petals deciduous. stamens 5 or 10, inserted on the calyx- 
tube at its union with the ovary: carpels united at base and adnate 
to the calyx-tube. 
