SAXIFRAGACEJE. (SAXIFRAGE FAMILY.) 173 



9. PARNASSIA, Tourn. GRASS OF PARXASSCS. 



Sepals 5, imbricated in the bud, slightly united at the base, and sometimes 

 also with the base of the ovary, persistent. Petals 5, veiny, spreading, at length 

 deciduous, imbricated in the bud ; a cluster of somewhat united gland-tipped 

 sterile filaments at the base of each. Proper stamens 5, alternate with the 

 petals, persistent; anthers introrse or subextrorse. Ovary 1-celled, with 4 

 projecting parietal placentas ; stigmas 4, sessile, directly over the placenta?. 

 Capsule 4-valved, the valves bearing the placenta; on their middle. Seeds 

 very numerous, anatropous, with a thick wing-like seed-coat and little if any 

 albumen. Embryo straight ; cotyledons very short. Perennial smooth herbs, 

 with entire leaves, and solitary flowers on long scape-like stems, which usually 

 bear a single sessile leaf. Petals white, with greenish or yellowish veins. 

 (Named from Mount Parnassus ; called Grass of Parnassus by Dioscorides.) 



1. P. parvifldra, DC. Petals sessile, little longer than the calyx (3" 

 long) ; sterile filaments about 7 in each set, slender; leaves ovate or oblong, ta- 

 pering at base. Sandy banks, Lab. to Mich., N. Minn., and westward. 



2. P. palllstris, L. Scapes 3-10' high; leaves heart-shaped; flower 

 nearly 1' broad; petals sessile, rather longer than the calyx, few-veined; ster- 

 ile filaments 9-15 I'M each set, slender. Same range as the last. (Eu.) 



3. P. Caroliniana, Michx. Scapes 9' -2 high; flower l-l' broad; 

 petals sessile, more than twice as long as the calyx, many-veined ; sterile fila- 

 ments 3 in each set, stout, distinct almost to the base ; leaves thickish, ovate or 

 rounded, often heart-shaped, usually but one low down on the scape and clasp- 

 ing. Wet banks, N. Brunswick to Fla., west to Minn., Iowa, and La. 



4. P. asarifolia, Vent. Petals abruptly contracted into a claw at base; 

 sterile filaments 3 in each set; leaves rounded, kidney-shaped ; otherwise as in 

 the foregoing. High mountains of Va. and N. C. 



10. HYDRANGEA, Grouov. 



Calyx-tube hemispherical, 8 -10- ribbed, coherent with the ovary; the limb 

 4 - 5-toothed. Petals ovate, valvate in the bud. Stamens 8-10, slender. Cap- 

 sule 15-ribbed, crowned with 2-4 diverging styles, 2-celled below, many -seeded, 

 opening by a hole between the styles. Shrubs, with opposite petioled leaves, 

 no stipules, and numerous flowers in compound cymes. The marginal flowers 

 are usually sterile and radiant, consisting merely of a showy membranaceous 

 and colored flat and dilated calyx. (Name from vStap, water, and &yyos, a vase, 

 from the shape of the capsule.) 



1. H. arborescens, L. (WILD HYDRANGEA.) Glabrous or nearly so, 

 1-8 high ; leaves ovate, rarely heart-shaped, pointed, serrate, green both sides; 

 cymes flat ; flowers often all fertile, rarely all radiant. Rocky banks, Penn. 

 to Fla., west to Iowa and Mo. 



2. H. radiata, Walt. Leaves dense! i/ tomentose and paler or white be- 

 neath. S. C. and Ga. to Tenn. and Mo. 



11. DECUMARIA, L. 



Flowers all fertile. Calyx-tube turbinate, 7- 10-toothed, coherent with the 

 ovary. Petals oblong, valvate in the bud. Stamens 20-30. Styles united 



