



SAXIFRAGACEAE (SAXIFRAGE FAMILY) 445 



1. A. biternata (Vent.) Britton. Somewhat pubescent (1-2 m. high); leaf- 

 lets mostly heart-shaped ; petals minute or wanting in the fertile flowers ; 

 stamens 10. (A. decandra Don.) Mt. woods, s. e. Ky. (Kearney} and s. w. 

 Va. to N. C. and Ga. Closely imitating Aruncus Sylvester, but coarser. 



2. SULLIVANTIA *T. & G. 



Calyx bell-shaped, adhering below only to the base of the ovary, 6-cleft. 

 Petals 5, oblanceolate, entire, acutish, withering-persistent. Stamens shorter 

 than the petals. Capsule 2-beaked, many-seeded, opening between the beaks ; 

 seeds imbricated upward. Low and reclined-spreading perennial herbs with 

 rounded and cut-toothed or slightly lobed smooth leaves on slender petioles, 

 and small white flowers in a branched loosely cymose panicle raised on a nearly 

 leafless slender stem (1.5-4 dm. long). Peduncles and calyx glandular; pedicels 

 recurved in fruit. (Dedicated to the distinguished bryologist William Starling 

 Sullivant, who discovered our species.) 



1 . S. Sullivantii (T. & G. ) Britton. (S. ohionis T. & G.) Limestone cliffs, 

 O. and Ind. to la. and Minn. June. 



3. BOYKINIA Nutt. 



Calyx-tube top-shaped, adherent to the 2-celled and 2-beaked capsule. Sta- 

 mens 5, as many as the deciduous petals, these mostly convolute in the bud. 

 Otherwise as in Saxifraga. Perennial herbs, with alternate palmately 5-7-lobed 

 or cut petioled leaves, and white flowers in cymes. (Dedicated to the late Dr. 

 Boijkin of Georgia.) 



1. B. aconitifblia Nutt. Stem glandular (2-6 dm. high); leaves deeply 

 6-7-lobed. ( Therofon Millspaugh.) Rocky banks, W. Va. (ace. to Millspaugh) 

 and mts. of Va. to Ga. and Tenn. July. 



4. SAXIFRAGA [Tourn.] L. SAXIFRAGE 



Calyx either free from or adhering to the base of the ovary, 5-cleft or 

 parted. Petals entire, imbricated in the bud, commonly deciduous. Styles 2. 

 Capsule 2-beaked, 2-celled, opening down or between the beaks, or sometimes 

 2 almost separate follicles. Chiefly perennial herbs, with the root-leaves clus- 

 tered, those of the stem mostly alternate. (Name from saxum, a rock, and 

 frangere, to break ; many species rooting in the clefts of rocks.) 



Acaulescent, the principal leaves in a basal rosette ; scapes naked below 

 the inflorescence. 



Flowers mostly replaced by leafy tufts 1. S. stellaris, v. comosa. 



Flowers all perfect. 

 Sepals reflexed. 

 Leaves conspicuously and coarsely dentate. 



Petals unequal ; follicles strongly ribbed 2. S. leucanthemifolia. 



Petals uniform ; follicles obscurely or not at all ribbed. 

 Leaves abruptly contracted to long petioles . . . 3. S. caroliniana. 



Leaves gradually narrowed to the base 4. S. micranthidifolia. 



Leaves finely or shallowly crenate-dentate. 



Leaves rnembranaceous, pilose beneath 5. S. Forbesii. 



Leaves leathery, glabrate beneath 6. S. pennsylvanica. 



epals ascending. 



Petals white, exceeding the sepals 7. S. virginiensis. 



Petals green, much shorter than the sepals, or wanting (7) S. cirginiensis, v. ehlorantha. 

 uilescent tufted or matted plants, branching at base, the flower- 

 ing branches mostly leafy below the inflorescence. 

 Leaves with 3-5 lobes or coarse teeth. 



Leaves (basal) rounded, on slender petioles 8. S. rivularis. 



Leaves gradually narrowed to the base, rigid, with 8 sharp teeth . 9. S. tricuspidata. 

 Leaves entire or with regularly many-toothed or ciliate margins. 

 Leaves linear-lanceolate, entire (sometimes sparingly ciliate), alter- 

 nate ; flowers yellow 1(J. S. aieoides. 



Leaves toothed or cfltale. 

 Leaves mostly in basal rosettes ; scapes upright, bearing numerous 



whitish tfowers 11. 5. Aizoon. 



Leaves crowded and opposite along the matted branches ; flowers 



solitary, purple 12. 8. oppositfolia. 



