124 ROSACEAE 



Sepals oval or broadly ovate, rarely lanceolate, rounded and mucronate at the apox. 

 Petals 7-8 mm. long, ascending in anthesis; leaves densely hairy; plant stout. 



1. Z>. agrimonioides. 

 Petals less than 6 mm. long, spreading or reflexed in anthesis. 



Petals ■i-6 mm. long ; calyx and hypanthium in fruit together 10-12 mm. long ; 



petioles conspicuously long-hairy; petals yellow. 12. D. oregana. 

 Petals 2—4 mm. long; calyx and hypanthium in fruit together 6-10 mm. long; 

 petioles mostly short-hairy; petals whitish. 

 Petals obovate; sepals twice as long as broad. 13. D. alMda. 



Petals orbicular or nearly so ; sepals half longer than broad. 



14. D. micropetala. 

 Style filiform or nearly so, more than twice as long as the ovary; plant about 2 dm. high; 

 petals much exceeding the sepals; leaflets rhomblc-obovate. 15. D. rhomboidea. 



19. CHAMAERHODOS Bunge. l. C. Nuttallii. 



20. SANGUISORBA L. Burnet. l. S. sitchensis. 



21. POTERIDIUM Spach. l. P. occidentale. 



22. AGRIMONIA L. Agrimony. 



Fruiting hypanthium with several series of bristles, the lower bristles reflexed; sepals 

 acuminate with tips incurved in fruit. 1. A. gryposepala. 



Fruiting hypanthium with 2—4 series of bristles, the latter erect, ascending or merely 

 spreading; sepals acute. 2. A. striata. 



23. COLEOGYNE Torr. Black Bush. l. P. ramoissima. 



24. WALDSTEINIA Willd. Bakhen Strawberry. l. W. idahoensis. 



26. DRYAS L. Dryad, Mountain Avbns. 



Sepals linear or linear-lanceolate; petals white, spreading. 



Leaf-blades entire or with a few acutish teeth, shining and not conspicuously rugose 



above, broadest near the base. 1. D. integrifoha. 



Leaf-blades coarsely round-crenate, dull, strongly rugose and impressed-reticulate ' 

 above, broadest near the middle. 2. D. octopetala. 



Sepals ovate or ovate-lanceolate: petals yellow, strongly a.scending. 



Hypanthium and calyx densely hairy with black glandular hau^s, only slightly to- 

 mentose. 3. D. Drummondii. 



Hypanthiimi and calyx densely white-tomentose, not glandular. 4. D. tomentosa. 



26. GEUM L. Avens. 



Sepals reflexed; upp*r internode of the style less than one-third as long as the lower. 

 Petals white or ochroleucous; receptacle long-hairy; hairs at least half as long as the 



achenes. 1. G. ca71adcn.se. 



Petals bright or golden yellow; receptacle short-hairy. 



Leaflets of the stem-leaves decurrent on the rachls, the upper ones confluent. 



2. G. decurrens. 

 Leaflets of the stem-leaves not decurrent. 



Upper internode of the style hirsute, the hairs about 1 mm. long ; lower inter- 

 node hirsute below, not glandular; petals orbicular, rounded at the base. 



3. G. strictum. 

 Upper internode of the style short-hispidiilous at the base or glabrous ; petals 



usually cuneate at the base, except in G. perincisum; lower internode 

 of the style glandular-pubenilent. 

 Divisions of the upper stem-leaves ample, rhombic or cuneate; inflores- 

 cence corymbiform, usually with short branches. 4. G. macrophyllum. 

 Divisions of the upper small stem-leaves oblanceolate or rarely obovate; 

 inflorescence open, with slender branches. 

 Leaflets doubly serrate or dentate; terminal leaflet of the basal leaves 



rounded or reniform. 5. G. oregonense. 



Leaflets especially those of the upper leaves deeply incised; terminal 

 leaflet of the basal leaves rhombic, ovate, or subcordate. 



6. G. perincisum. 

 Sepals ascending or merely spreading; upper internode of the style at least half as long 

 as lower Internode, hirsute; petals flesh-colored, piu-ple-veined. 7. G. rivale. 



27. SIEVERSIA WiUd. Old Man's Whiskers. 

 LeEkflets cuneate, toothed at the apex. 



Hypanthium at least in flower acute at the base; bractlets much exceeding the lance- 

 olate sepals; petals eUiptic. 1. s. trifiora. 

 Hypanthium in flower rounded or sunken at the base; bractlets about egualliiig or 

 shorter than the ovate or ovate-lanceolate sepals; petals broadly elliptic. 

 Bractlets linear or Unear-subulate, equalling the sepals or sUghtly exceemng them. 



2. S. grisea. 

 Bractlets oblong-Unear or lanceolate, shorter than the sepals. 3. S. canescens. 



Leaflets dissected at least half way into linear or linear-lanceolate divisions. 



