SAXIFRAGACE.E. (SAXIFRAGE FAMILY.) 173 



9. PARNASSIA, Touru. Grass of Parnassus. 



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 glaud-tipped 

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

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

 projecting parietal placentae ; stigmas 4, sessile, directly over the placentae. 

 Capsule 4-valved, the valves bearing tlie placentae on their middle. Seeds 

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

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

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

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

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



1. P. parvifl6ra, iK\ Petals sessile, little longer than the calyx (3" 

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

 })ering at base. — Sandy banks, Lab. to Mich., N. Minn., and w^estward. 



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

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

 ile Jilame)its 9-15 in each set, slender. — Same range as the last. (Eu.) 



3. P. Carolini^na, Michx. Scapes 9' -2° high; flower 1-1^' broad; 

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

 inents 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 abruptli/ contracted into a r/(;/r at base ; 

 sterile Jil anient s 3 in each set ; leaves rounded, kidney-shaped ; otherwise as in 

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



10. HYDRANGEA, Gronov. 



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 1.5-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 flowerii 

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

 and colored flat and dilated calyx. (Name from uSwp, ivater, and 6770s, 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. U. radiata, Walt. Leaves densely tomentose and paler or ichite ba 

 neath. — S. C. ami (ia. to Teun. and Mo. 



11. DECUMAIIIA, L. 



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

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



