SAXIFRAGE FAMILY 387 



High mountains: Greenl. — Lab. — Que. — B.C.^Alaska; Eu. Alp. — Subalp. 

 Je-Au. 



18. CHONDROSEA Haw. 



Perennial caulescent herbs, witli a den.seh- leafy short caudex and offsets, and 

 sparingly leafy flower-stalks. Leaves alternate; blades serrate, each tooth 

 terminating in an encrusted pore. Flowers in terminal compound cymes. 

 Hypanthium turbinate to campanulate, at maturity longer than the calyx. 

 Sepals 5, erect. Corolla white, regular. Petals 5, clawless. Stamens 10; fila- 

 ments lanceolate or lanceolate-subulate. Ovary about half-inferior, the carpels 

 united to above the middle. Follicles united to the spreading tips. 



1. C. Aizoon (Jaccj.) Haw. Stems 1-4 dm. tall; basal leaves linear-oblong 

 to spatulate, 1.5-4 cm. long; stem-leaves few, remote, more abruptly bi-oadened 

 than those on the caudex; sepals ovate, 1.5-2 mm. long; petals oval, oval-obo- 

 vate or oval-oblong, 3.5-4 mm. long, sessile. Saxifraga Aizoon Jacq. Wet 

 rocks: Lab. — -N.S. — Vt. — -Sask. ; Eurasia. Boreal — Subarctic. Je-Jl. 



19. MICRANTHES Haw. Saxifrage. 



Perennial acaiilescent herbs, with very short caudices and solitary or tufted 

 scapes, sometimes bulblet-bearing at the base. Leaves basal; blades fleshy, entire 

 or toothed. Flowers in terminal cymes disposed in narrow or broad panicles. 

 Hypanthium rather flat, shorter than the calyx. Sepals 5, erect or reflexed. 

 Corolla essentially regular. Petals 5, mostly white. Stamens 10. Ovary 

 slightly inferior, the carpels partially united, often only at the base. Folhcles 

 spreading or with spreading tips. 



Filaments subulate or filiform-subulate, or sometimes narrowly linear. 



Cymules wholly or mainly aggregate into a head or spike, 1 or 2 lower ones some- 

 times remote or peduncled. 

 Petals shorter than the sepals or about equalling them. 



Lower cymules sessile; petals about equalling the sepals. 1. M. Rydbergii. 

 Lower cymules peduncled; petals shorter than the sepals. 



Petals obovate to oval or orbicular-oval. 2. M. crenatifolia. 



Petals oblong to cuneate. 3. M. Columbiana. 



Petals larger than the sepals. 



Sepals ovate to triangular. 



Sepals oval, rounded at the ape.x. 



Cymules in narrow pyramidal panicles. 



Corolla present. 



Petals white. 



I^eaves with blades narrowed into petiole-like bases. 

 Leaves without petiole-Uke bases. 



Panicle wide ; peduncl&s of the lower cymules elongate. 

 Petals with claw-like bases. 

 Petals without claw-like bases. 

 Panicle narrow; peduncles permanently very short. 

 Petals greenish. 

 Corolla wanting or obsolete. 

 Filaments clavate or spatulate. 

 Leaf-blades flabellate. 

 Leaf-blades ovate, oval, broadly oblong, or orbicular. 



Leaf-blades narrowed at the base, neither cordate nor of an orbicular type. 



Cymules permanently compact. 13. M. occidentalis. 



Cymules lax and open. 14. M. saximontana. 



Leaf-blades orbicular or nearly so. 



Petals with elhptic-oblong or ovate blades, the claws stout. 1.5. ^f. aestivalis. 

 Petals with suborbicular or reniform blades, the claws slender. 



16. ^f. arguta. 



1. M. Rydbergii Small. Leaves spreading, 2-4 cm. long, oblong to ovate, 

 obtuse, undulate or repand-dentate, glabrous or nearly so, paler beneath; scapes 

 solitary, erect, 5-10 cm. tall, purplish, glandular-puberulent ; sepals ovate or 

 triangular-ovate; petals oblong-oval, 1-1.5 mm. long. Saxifraga Rydbergii 

 Small. Mountain summit: Mont. Alp. Au. 



2. M. crenatifolia Small. Leaves spreading, 2-3 cm. long, obovate, cune- 

 ate or orbicular-flabellate, coarsely crenate, glabrous or nearly so; scapes 

 erect, about 15 cm. tall, closely glandular-pubescent; sepals deltoid or ovate- 

 deltoid, obtuse; petals about 1.5 mm. long, roimded at the apex. S. crenatifolia 

 Fedde. High moimtains: Mont. — B.C. Mont. My-Jl. 



