Genus ii. 



ROSE FAMILY. 



261 



5. Fragaria americana (Porter) Brit- 

 ton. American Wood Strawberry. 

 Fig. 2256. 



Fragaria vesca var. americana Porter, Bull. Torr, 



Club 17 : 15. 1890. 

 Fragaria americana Britton, Bull, Torr. Club 19 : 



222. 1892, 



Slender, light green, loosely villous-pubes- 

 cent or glabrate, usually producing runners 

 more freely than any of the preceding species. 

 Leaflets thin, ovate or oval, obtuse or acute 

 at the apex, sharply incised-dentate, the ter- 

 minal one commonly cuneate, the others in- 

 equilateral at the base, pubescent with silvery 

 appressed hairs beneath ; flowers smaller than in 

 F. vesca; calyx-lobes spreading or reflexed in 

 fruit; fruit ovoid or elongated-conic, light red 

 or pink, the achenes borne on its glabrous 

 shining even surface and but slightly attached 

 to it. 



In rocky woods, Newfoundland to Manitoba, 

 Virginia and New Mexico. May-June. 



12. SIBBALDIA L. Sp. PI. 284. 1753. 



Depressed alpine or arctic shrubby plants, with alternate mainly 3-foliolate stipulate 

 leaves, and cymose flowers on scape-like nearly leafless peduncles. Calyx slightly concave, 

 5-lobed, 5-bracteolate, persistent. Petals 5, oblong or oval, much smaller than the calyx-lobes, 

 yellow. Stamens 5, opposite the calyx-lobes, inserted on the margin of the villous-pubescent 

 disk. Carpels 5-10, on short pubescent stipes; style lateral. Achenes S-io, glabrous. 

 [Named in honor of Robt. Sibbald, a Scotch naturalist.] 



About S species, natives of the colder parts of the north temperate zone. The following typical 

 one is the only known American species, 



I, Sibbaldia procumbens L. Sibbaldia. 

 Fig. 2257. 



Sibbaldia procumbens L. Sp. PI. 2S4. 17 S3- 



Potentilla procumbens Clairv. Man. Herb, Suisse 166. 181 1. 



Densely tufted, stem woody, decumbent or creeping, 

 a few inches long. Stipules membranous, lanceolate 

 or ovate-lanceolate, adnate; leaves 3-folioIate; petioles 

 slender, 2'-^' long; leaflets obovate or oblanceolate, 

 cuneate at the base, 3-S-toothed at the apex, pubescent 

 with scattered hairs on both sides, resembling in out- 

 line those of Sibbaldiofsis tridentata; peduncles axil- 

 lary, nearly naked, about equalling the leaves ; flowers 

 yellow, about 2i" broad, numerous; petals oblong or 

 oval, very small ; calyx-lobes oblong-ovate, acute, longer 

 and broader than the bractlets. 



Summits of the White Mountains ; Mt, Albert, Quebec ; 

 Labrador, Greenland, arctic America to Alaska, south in 

 the Rocky Mountains to Colorado and Utah and to Cali- 

 fornia, Also in arctic and alpine Europe and Asia. Sum- 

 mer. 



13. SIBBALDIOFSIS Rydb. Mem. Dep. Bot. Col. Univ. 2 : 187. 



A depressed tufted shrub with thick trifoliolate leaves and small white flowers in ter- 

 minal cymes. Calyx-tube nearly flat. Bractlets, calyx-lobes and petals 5. Petals obovate, 

 rounded, not clawed. Stamens about 20, borne in 3 series near the base of the receptacle ; 

 filaments filiform; anthers cordate. Receptacle hemispheric, bearing numerous pistils. Style 

 filiform, lateral. Achenes swollen, villous. Seed amphitropous, ascending. [Greek, from the 

 similarity of this plant to Sibbaldia procumbens.] 



A monotypic genus of eastern North America. 



