262 ROSACEAE (ROSE FAMILY) 



carpels numerous, sessile on the spongy receptacle. Marshy ground; northern 

 Wyoming to the arctic circle. 



25. GEUM L. AVENS 



Perennial herbs with large, mostly radical, lyrate or pinnate leaves (those 

 of the stem much smaller), and stipules adnate to the sheathing petioles. 

 Flowers corymbosely cymose or solitary. Calyx persistent, 5-lobed, and 

 5-bracteolate. Petals 5. Stamens numerous, inserted on a disk at the base 

 of the calyx. Pistils numerous; the style persistent, straight or (in ours) 

 jointed, hooked or sometimes plumose in fruit. Achenes small, compressed, 

 on a small conical or clavate receptacle. 



Sepals reflexed; upper part of style deciduous. 



Terminal leaflet cuneate-obovate; receptacle downy-pubescent . 1. G. stnctum. 



Terminal leaflet broadly cordate; receptacle nearly naked . . 2. G. macrophyllum. 



Sepals erect; upper part of style persistent and plumose in fruit . 3. G. rivale. 



1. Geum strictum Ait. Hort. Kew 2: 217. 1789. Stems erect, pubescent, 

 3-8 dm. high: root leaves interruptedly pinnate; the leaflets obovate-cuneate; 

 stem leaves few, 3-5-f oliolate ; the leaflets rhombic-ovate or oblong, acute: 

 flowers yellow, terminal, short-peduncled : carpels compressed, hairy at sum- 

 mit or on the base of the hooked style: receptacle downy-pubescent. (G. 

 scopulorum Greene, Pitt. 4: 148. 1900.) From Colorado northward, and east- 

 ward to the Atlantic. 



2. Geum macrophyllum Willd. Enum. 557. 1809. Bristly-hairy, stouter, 

 3-5 dm. high: root leaves lyrately and interruptedly pinnate, with the ter- 

 minal leaflet very large and round heart-shaped; the lateral leaflets of the 

 stem leaves minute, 2-4; the terminal one roundish, 3-cleft, the lobes cuneate- 

 obovate: flowers yellow, in a terminal cyme; the petals obovate, longer than 

 the acute calyx-lobes: receptacle nearly glabrous: style hooked, obscurely 

 glandular (the minute glands short-stipitate), pubescent near the base. (G. 

 oregonense Rydb. Bull. Torr. Bot. Club 25: 56. 1898.) From California to 

 the Atlantic. 



3. Geum rivale L. Sp. PI. 501. 1753. Somewhat pubescent, erect, 3-5 dm. 

 high: stem nearly simple: root leaves lyrate and interruptedly pinnate; those 

 of the stem few, 3-f oliolate or 3-lobed: calyx brown-purple: petals dilated- 

 pbovate, retuse, contracted into a claw, purplish-orange : head of fruit stalked 

 in the calyx: achenes very pubescent; styles jointed, plumose. Colorado 

 and northward, and east to Newfoundland. 



26. SIEVERSIA Willd. 



Rather low perennial herbs, with simple stems, mostly radical pinnate 

 leaves, and rather large flowers in terminal cymes. Sepals, bractlets, and petals 

 5. Sepals erect or spreading. Style not jointed, straight, slender, persistent 

 and often plumose; head of carpels sessile. 



Clammy, short-pubescent and hirsute or ciliate; style plumose . . 1. S. ciliata. 

 Nearly glabrous; style glabrous. 



Stem Ir.Hvi-s pinniititid; root leaves mostly subereet . . . . 2. S. turbinata. 



Stem Ic.-ivt-.s entire; root leaves rosulate-spreading . . . .3. S. scapoidea. 



1. Sieversia ciliata G. Don. Gen. Hist. 2: 528. 1832. Somewhat clammy, 

 abort-pubescent and more or less softly hirsute or ciliate: leaves mostly basal, 

 suherect, interruptedly pinnate; the leaflets very numerous and crowded, 

 CMineate-obovale in outline, deeply incised, often nearly to the midrib: steins 

 simple, merely leafy-l>racteate, terminating in the mostly 3-flowered cyme: 

 flowers long-pediceled: calyx purple, its linear bractlets longer than the se- 

 pal- and as long as the purplish erect petals: styles very long, strongly plumose 

 in fruit. Geum triflornm. Moist slopes in the mountains; common in our 

 \vhole range. 



2. Sieversia turbinata (Rydb.) Greene, Pitt. 4: 50. 1899. Low, 7-15 cm. 



