ROSACEAE (ROSE FAMILY) 263 



high, glabrate or more or less puberulent, especially above: leaves mostly 

 basal, interruptedly pinnate, spreading or suberect, dark green or tinged with 

 purple; leaflets ovate-cuneate or narrower, incisely toothed; stem leaves 

 pinnately incised: stems surpassing the leaves, rarely nearly twice as long, 

 1-3-flowered: calyx dark- or purplish-green; the triangular lobes scarcely 

 longer than the lanceolate bractlets, much surpassed by the obovate bright 

 yellow petals: style glabrous, not exserted in fruit; achene villous-hirsute. 

 Geum Rossii. Alpine; in Colorado, Utah, and Wyoming. 



3. Sieversia scapoidea A. Nels. Glabrous (obscurely puberulent under a 

 strong lens): leaves rosulate-spreading from the crowns of a more or less 

 branched woody rootstock, interruptedly pinnate, 5-10 cm. long; leaflets ob- 

 ovate, 3-cleft into oblong, subacute lobes, not crowded: stems scapose, few, 

 erect, strictly 1-flowered, 14-20 cm. high; the bract-like leaves entire, linear, 

 15-20 mm. long, the rather large stipules long-adnate: flowers large, 2 cm. 

 broad: calyx softly pubescent, its triangular-lanceolate lobes longer than its 

 tube; the bractlets minute, nearly linear: petals obovate-orbicular, pale yellow, 

 twice as long as the calyx: achene tapering gradually into the style, long- 

 hirsute as is also the thickened base of the style. Utah. 



27. AGRIMONIA L. AGRIMONY 



Tall perennial herbs, with interruptedly pinnate leaves, and flowers with 

 3-cleft bracts, in long slender spicate racemes. Calyx turbinate, surrounded 

 by a margin of hooked prickles. Petals yellow, small. Stamens 5-12. Car- 

 pels 1-3, becoming achenes, inclosed in the dry and firm calyx-tube which is 

 constricted at the throat and its 5 lobes connivent. 



1. Agrimoni^ Brittoniana Bickn. Bull. Torr. Bot. Club 23: 517. 1896. 

 Stout, 4-7 dm. high, virgately branched, hirsute: leaflets 7-11, with smaller 

 leaf-segments interposed, elliptic-oblong, acute, sharply serrate; stipules 

 lanceolate, acuminate: flowers crowded: fruit 8 mm. long, reflexed; the bris- 

 tles often purplish, inflexed. A. Eupatoria. Colorado to Montana, east to 

 New York. 



28. SANGUISORBA L. 



Annual or perennial herbs, with alternate, pinnatifid, stipulate leaves and 

 small perfect flowers in dense, terminal, peduncled spikes or heads. Calyx- 

 lobes 4, imbricated, deciduous, petaloid; calyx-tube 4-angled, naked. Petals 

 wanting. Stamens 2-12, inserted on the throat of the calyx. Carpels usually 

 only 1, inclosed in the dry, 4-wing-angled calyx. Poterium. 



1. Sanguisorba annua Xutt. T. & G. Fl. N. A. 1: 429. 1840. Glabrous, 

 slender, 2-4 dm. high: leaflets 4-6 pairs, ovate to oblong, with linear segments: 

 flowers greenish; the heads ovoid or oblong: stamens 2-4: fruits shorter than 

 the bracts. Poterium annuum. Possibly within our range ; said to occur from 

 the upper Missouri to Oklahoma and in California to Washington. 



29. ROSA (Tourn.) L.* ROSE 



Shrubby more or less prickly plants, with pinnate leaves and large flowers 

 solitary at the ends of the branchlets or^in few-flowered corymbs. Stipules 

 adnate to the petiole. Calyx without bractlets. Stamens numerous on the 

 thick margin of the silky disk which nearly closes the throat of the calyx. 

 Carpels many, hairy, becoming bony achenes inclosed and concealed in the 

 globose or urn-shaped fleshy calyx-tube, which resembles a pome. 



* There are few genera in which the species are so difficult of discrimination. The species 

 as given here are no doubt, in some cases at least, " group species," hut it does not seem 

 possible in the present state of our knowledge so to characterize the different forms as to 

 make them distinguishable, 



