SAXIFRAGACE&. 225 



Order XXIX. SAXIFRAGACE^E (Saxifrage Family). 



Herbs, or shrubs. Leaves alternate, or opposite, sometimes 

 stipulate. Sepals 4 or 5, more or less cohering, persistent. Pet- 

 als 4 or 5, inserted between the calyx-lobes, rarely wanting. Sta- 

 mens 5-10, inserted on the calyx-tube. Ovary adherent to the 

 calyx-tube, of 2, or sometimes 3-5 carpels, cohering below, distinct 

 above. Styles 2, sometimes 3-5. Fruit a I, or rarely 3~5-celled 

 capsule. 



Leaves alternate Ribes. 



Leaves f Stamens vo-qz-Philadelphus. 



opposite -| 



(^Stamens 8-10 Hydrangea. 

 SAXIFRAGACE^E. \ 



f Petals f Flowers in racemes Tiarella. 



I entire \ 

 I Flowers not in racemes Saxifraga, 

 Herbs- \ 



Petals pinnatifid 'Mitella. 



Petals none Chrysosplenium. 

 I. Saxifraga. Sepals 5, more or less united. Petals 5, inserted 

 on the calyx-tube, entire. Stamens 10. Anthers 2-celled, opening 

 longitudinally. Capsule of 2 carpels, 2-celled below, opening between 

 the 2 divergent beaks. Seeds numerous, y. 



1. S. VIRGINIENSIS (Early Saxifrage}. Leaves mostly radical, ovate, 

 spatulate, on broad petioles ; scape mostly naked ; flowers small, white, 

 numerous, cymose. Early flowering plant, on rocks and dry hills, scape 3'- 

 10' high. April-May. 



2. S. PENNSYLVANIA (Tall Saxifrage). Leaves radical, oval, rather 

 acute, tapering at base, with short, margined petioles ; scape almost leafless, 

 striate, viscid pubescent ; flowers yellowish-green, pedicellate ; petals linear- 

 lanceolate. In swamps and meadows, with hollow scapes 1-3 feet high. 

 May. 



2. Mitella. Calyx campanulate, 5-cleft. Petals 5, pinnatifid. 

 Stamens 5-10, included. Styles 2, short, distinct. Capsule i-cclled, 

 2-valved. y. 



M. DIPHYLLA (Common Mitella). Stem simple, pubescent; leaves cor- 

 date, serrately toothed, pubescent ; flowers white, in long, terminal racemes 

 on short pedicels, beautifully marked by the pectinate petals ; styles short. 

 A plant 6'-i2' high. May-June. 



3. Tiarella. Calyx 5-parted, with obtuse lobes, valvate in preflora- 

 tion. Petals 5, entire. Stamens 10, inserted with the petals. Styles 

 2. Capsule i-celled, 2-valved. y. 



T. CORDIFOLIA (Mitreworf). Acaulescent ; leaves cordate, acutely 3-5- 

 lobed, dentate, with mucronate teeth, hirsute above ; stolons creeping; flow- 

 ers white, in racemes ; bracts minute ; petals oblong. May-June. 



