VOL. II.] 



ROSE FAMILY. 

 10. COMARUM L,. Sp. PI. 502. 1753. 



217 



A stout dark green nearly glabrous herb, with alternate pinnate large-stipuled leaves, the 

 large purple flowers cymose or solitary, terminal or also axillary. Calyx deeply 5-lobed, 5- 

 bracteolate, the bractlets narrow. Petals shorter than the calyx-lobes, acute, purple. 

 Stamens numerous, inserted on the large pubescent disk. Pistils numerous, inserted on the 

 pubescent receptacle which becomes spongy in fruit. Style lateral. Achenes glabrous, 

 i-seeded. Seed pendulous. [Greek name of the Arbutus, from the similar fruits.] 



A monotypic genus of the north temperate zone. 



i. Comarum palustre L,. Purple or 



Marsh Cinquefoil. Purple Marshlocks. 



Cowberry. (Fig. 1937.) 



Comarum palustre L- Sp. PI. 502. 1/53. 



Potentilla palustris Scop. Fl. Carn. Ed. 2, i: 359. 1772. 



Decumbent and somewhat woody at the base, the 

 upper part of the stems pubescent. Leaves pinnate, 

 the lower long-petioled, 5-y-foliolate; leaflets ob- 

 long or oval, sharply or incisely serrate, obtuse or 

 acutish at the apex, narrowed at the base, 1'-$' 

 long; stipules membranous, sometimes adnate to 

 the petiole for half its length; upper leaves nearly 

 sessile 3-5-foliolate; flowers showy, 9 // -i5 // broad; 

 calyx-lobes purple within, ovate, acuminate, much 

 exceeding the ovate-lanceolate petals; bractlets 

 much shorter than the calyx-lobes; disk lobed. 



In swamps and peat-bogs, Labrador to New Jersey, 

 Iowa, British Columbia and Alaska. Also in California, 

 northern Europe and Asia. June-Aug. 



ii. 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 5-10, glabrous. 

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



About 5 species, natives of the colder parts of the north temperate zone. The following is the 

 only known American species. 



i. Sibbaldia procumbens L/. Sibbaldia. 

 (Fig. 1938.) 



Sibbaldia procumbens L. Sp. PI. 284. 1753. 



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-foliolate; petioles 

 slender, Z'-A/ long; leaflets obovate or oblanceolate, 

 cuneate at the base, 3~5-toothed at the apex, pubescent 

 with scattered hairs on both sides, resembling in out- 

 line those of Potentilla tridentata; peduncles axillary, 

 nearly naked, about equalling the leaves; flowers yel- 

 low.about 2^ x/ 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 Utah. Also in arctic and alpine 

 Europe and Asia. Summer. 



