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Aquatic and Wetland Vascular Plants of the Northern Great Plains

Parnassia L. -- Grass-of-Parnassus


Single or clumped, glabrous perennials. Leaves all basal except 1 sessile leaf usually present near or below the middle on each scape, the blades entire; petioles winged at the base by the elongate brownish stipules. Flowers rather showy, white, solitary on the scapes; calyx usually adnate to the ovary in the connate lower portion, the sepals acute to rounded; petals white, strongly nerved; functional stamens 5, inserted on the hypanthium opposite the sepals and alternating with 5 staminodes which are opposite the petals, staminodes dilated from the base and divided into 3-many filamentlike segments tipped with glandular knobs, shorter than to slightly exceeding the functional stamens; pistil 4-carpellary, stigmas 4, sessile or nearly so, ovary superior to slightly inferior; hypanthium very short. Capsule 4-valved, containing numerous oblong, angular seeds.

Lead Characteristic Go To
1 Staminodes 3-parted; sepals with a narrow hyaline margin. P. glauca
1 Staminodes (5)7- to many-parted; sepals herbaceous throughout. Lead 2
2 Leaf blades ovate to subrotund, broadly rounded to usually cordate at the base, not decurrent on the petiole; bract-leaf often clasping; petals 7- to 11-nerved. P. palustris
2 Leaf blades elliptic to elliptic-ovate, tapered to and decurrent on the petiole; bract-leaf not clasping; petals usually 5(7)-nerved. P. parviflora


25. Saxifragaceae, the Saxifrage Family
2. Parnassia L. -- Grass-of-Parnassus
1. Parnassia glauca Raf.
2. Parnassia palustris L.
3. Parnassia parviflora DC.


Return to Family -- Saxifragaceae - The Saxifrage Family
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