SAXIFRAGACE^K. 127 



Springs and brooks. Can. to Car. April, May. "L[. Plant succulent, creep* 

 ing, with small sessile flowers. Calyx usually 4- cleft. Stamens mostly 8. Seeds 

 hispid, reddish-brown. Hooker, Darlington, Torrey and Gray, consider our 

 plant different from C. opposili folium of Europe. 



American Golden Saxifrage. 



3. MITELLA. Linn. Bishop's-Cap. 



(A diminutive of the Latin nritra. a mitre or cop ; in allusion to the form of 

 the capsule.) 



Calyx campanulate, 5-cleft. Petals 5, inserted into the calyx, 

 laciniate or toothed. Stamens 10. Styles 2, united. Stigmas 

 scarcely distinct. Capsule 1 -celled, 2-yalved; valves equal. 

 Seeds numerous. 



1. M. diphylla Linn. : radical leaves cordate-lobed, toothed and ciliatc; 

 cauline ones 2, opposite, smaller ; flowers in a terminal raceme ; petals 

 toothed-pin natifid ; calyx and capsule at length membranaceous. 



On wet. rocks. Can. and N. S. W. to Mich, and Ken. April, May. '2J.. 

 Stem 8 10 inches high. Radical leaves on long petioles ; cauline one ssessile, 

 Flowers small, white. Two-leaved Bishop' s-cap. 



2. M. cordifolia Linn. : radical leaves cordate, sub-3-lobed, doubly cre- 

 nate ; scape naked or with a single leaf, scaly at base ; petals fimbriate- 

 pinnatifid. M. nuda Linn. Torr. <$ Gr. M. reniformis Lam. 



Moist rocks. N. S. N. to Arct. Amer. W. to the Rocky Mountains. June. 

 Scape 6 8 inches high, sometimes prostrate with creeping suckers. Radical 

 leaves on long petioles ; cauline one much smaller and sessile. Flowers few, 

 greenish-white, in a terminal spike. Heart-leaved Bishop's-cap. 



4. TIARELLA. Linn. Mitrewort. 



(A diminutive of the Latin tiara, a head-dress ; in allusion to the form of the 

 capsule.) 



Calyx 5-parted, persistent, with the lobes obtuse. Petals 5, 

 inserted into the calyx, unguiculate, entire. Stamens 10. 

 Styles 2, distinct. Capsule 1 -celled, 2-valved ; valves unequal. 

 Seeds few, near the base of the capsule. 



T. cordifolia Linn. : scape naked ; leaves cordate, acutely lobed, un- 

 equally dentate with mucronate teeth ; petals with long claws. 



Shady woods. Can. to Virg. April, May. 1\.. Scape 8 10 inches high, 

 sending out stolons after flowering. Radical leaves on long petioles. Flowers 

 white, in a simple terminal raceme. Heart-leaved Mitrewort. 



5. HEUCHERA. Linn. Heuchera. 

 (In honor of John Henry Heucher, a German botanist.) 



Calyx campanulate, coherent with the ovary below, 5-cleft. 

 Petals 5, small, entire. Stamens 5, inserted alternately with the 

 petals into the throat of the calyx. Styles 2. Capsule with 

 2 beaks, 1 -celled, many-seeded. 



