164 SAXIFKAGE FAMILY. 



XXXIX. SAXIFRAGACEJ;, SAXIFRAGE FAMILY. 



A large family not readily defined by any single characters ; 

 distinguished generally from Rosace* by having albumen in 

 the seeds, ovaries partly or wholly united, and seldom any 

 stipules ; the herbs and most of the shrubs of the family have 

 only as many or twice as many stamens, and fewer styles or 

 stigmas than there are petals or sepals. Flowers mostly per- 

 fect. Stamens and petals generally borne on the calyx, the 

 latter usually withering and persistent. Leaves alternate or 

 opposite. 



I. SAXIFRAGE SUBFAMILY. Herbs. Stipules none, 

 or confluent with the base of the petiole. Seeds usually many. 



* Stamens twice the number of the petals or the lobes of the calyx, mostly 10 ; pod com- 



monly 2-lobed, beaked, or 2, rarely 3-4, nearly separate pods. 

 j- Petals mostly 5, entire. 



1. SAXIFRAGA. Flowers in cymes or panicles, or rarely solitary, perfect. Leaves 



simple or palmately cut. Petals imbricated in the bud. Pod 2-celled below, or 2 

 (rarely more) separate pistils and pods, many-seeded. 



2. ASTILBE. Flowers in spikes or racemes collected in an ample compound panicle, 



sometimes polygamous or dioecious. Leaves ample, decompound. Petals small, 

 spatulate, or linear. Little pods 2 or 3, nearly separate, opening down the inner 

 suture, several-seeded. 



8. TIARELLA. Flowers in a raceme. Calyx colored (white), 5-parted, and in the sinuses 

 bearing 5 very narrow, slender-clawed petals. Filaments and styles long and slender. 

 Ovary 1-celled, with several ovules towards the base of the 2 parietal placentae, 

 2-beaked ; one of the beaks or carpels growing much more than the other and 

 making the larger part of the lance-shaped membranaceous pod, which is few- 

 seeded towards the bottom. 



+- +- Petals 5, pinnatifid, very delicate. 



4. MITELLA. Flowers in a simple raceme or spike, small. Petals colored like the short 



open calyx (white or green). Stamens short. Styles 2, very short. Ovary and pod 

 globular, 1-celled, with 2 parietal placentae at the base, many-seeded, opening across 

 the top. 



* * Stamens as many as the petals and alternate with them, usually 5, and a cluster of 



gland-tipped sterile filaments before each petal ; stigmas mostly 4, directly over 

 as many parietal placentce. 



5. PARNASSIA. Flower solitary, terminating a scape-like (usually 1-leaved) stem ; the 



leaves mostly from the root, rounded, smooth, and entire. Calyx free from the ovary 

 of 5 sepals. Petals 5, veiny, imbricated in the bud. Styles none. Pod 1-celled, 

 many-seeded. 



* * * Stamens only as many as the petals, 4 or 5 ; no sterile filaments ; styles 2 and 



alternate with the placentce or partition. 



6. HEUCHERA. Flowers small, in a long panicle, mostly on a scape. Calyx bell- 



shaped, the tube cohering below with the 1-celled ovary, and continued beyond it, 

 above 5-cleft, and bearing 5 small, spatulate, erect petals at the sinuses. Styles 

 slender. Pod 1-celled, 2-beaked at the apex, opening between the beaks. 



