Parnassiaceæ Grass-of-Parnassus Family

Smooth bog-herbs with a rosette of basal leaves and generally one or a few alternate stem leaves and solitary, terminal flowers. Flowers perfect; calyx generally 5-lobed to near the base; petals 5; perfect stamens 5; staminodia (imperfect stamens) in clusters at the base of each petal; stigmas 4.

Parnassia fimbriata Banks. Fringed Grass-of-Parnassus.

Leaves tufted at the base on petioles 2—6 inches long; blades reniform or broadly cordate, ¾—½ an inch wide, thin, smooth, with about 7 principal veins. Flowers ¾ of an inch or more broad on a scape 8—12 inches high with a small cordate clasping bract about the middle; sepals ¼ of an inch long, elliptic, obtuse; petals obovate, pure white, fringed at the base, staminodia united into 5 fleshy obovate scales.

Common throughout the region in springy places and damp mossy banks at the lower altitudes, flowering during July.

Parnassia montanensis Rydb. & Fernald. (½ Nat.) Marsh Grass of Parnassus.

Ribes lacustre (Pers.) Poir. (¼ Nat.) Swamp Gooseberry.

Parnassia montanensis Rydb. and Fernald. Marsh Grass-of-Parnassus.

Leaves tufted at the base on short petioles, blades ovate with a cordate or rounded base ¾ of an inch long. Flowers solitary, on scapes 8 inches or more high with a large ovate bract below the middle; sepals lanceolate, acute, ¼ of an inch or more long, petals oval to elliptic only slightly larger than the sepals; staminodial scales with 7—9 gland-tipped filaments.

Throughout the Rockies in marshy ground and shaded river shores; flowering in June and early July.

Parnassia parviflora DC. Small-flowered Grass-of-Parnassus.

Scapes slender, 4—12 inches high, usually bearing a clasping oval leaf at the middle. Basal leaves on slender petioles, oval or ovate, narrowed at the base, not cordate, ½—1 inch long. Flowers about ⅓ of an inch broad, sepals equalling or somewhat shorter than the elliptic sessile petals; staminodia 5—7 at the base of each petal.

In wet gravelly places at the lower altitudes throughout the Rockies; flowering in July.

Parnassia Kotzebuei Cham. and Schl. Alpine Grass-of-Parnassus.

Much smaller than the preceding species. Basal leaves few on petioles less than an inch long; blades broadly ovate, ½ an inch long. Flowers on slender scapes 2—4 inches high, without any bract; sepals oblong, about ¼ of an inch long, equalling or exceeding the elliptic or oval 3-veined petals; staminodia short with 3—5 slender filaments.

Throughout the Rockies at high altitudes on the gravelly borders of alpine ponds or brooks, a very diminutive species, flowering in July.