194 



MEMOIRS OF THE NEW YORK BOTANICAL GARDEN. 



Saxifraga nivalis L. Sp. PL 401 [Man. R. jM. 92 ; 111. Fl. 2 : 174; 



Bot. Cal. I : 194]. 



On top of the higher mountains, at an altitude of 2500 m. or more. 



Montana: Deer Lodge, F. W, Traphag-cn, iSSS: Missoula, 

 1883, Tweedy ; Upper Sand Coulee, 1888, R. S. Williams^ g; Old 

 Hollowtop, Pony, Juh' 9, 1897, Rydbcrg & Besscy, 426-/ : Cedar 

 Mt., July 16, 4.266. 



Yellowstone Park: Mammoth Hot Springs, 1893, F. H. 

 Bui'glchaus ; Sepulchre Mt., 1885, Tzvecdy, Sj/. 



* Saxifraga aprica Greene, Bull. Torr. Bot. Cluh. 23 : 25 ; Saxifraga 



unibellulata Greene, Erythea, i : 222. 



Resembling somewhat S. nivalis in habit. Characterized by the 

 numerous bulblets on the crown, spatulate-obovate petals and stout 

 filaments. It grows on mountains, at an altitude of nearly 3000 m. 



Montana : Mt. Chauvet, July 27, 1897, Rydbcrg d- Bessey, 426 j. 



Saxifraga integrifolia Hook. Fl. Bor. Am. i : 249 [Bot. Cal. i : 



194 : Man. R. M. 92] . 



On mountain sides, at an altitude of 2000-3000 m. 



Montana: Mullan Pass, 1889, ^' ^' Fchcy \ Bozeman, 1892, 

 W. T. Sha-io ; Bridger Mts., June 18, 1897, Rydbcrg tO Bessey, 

 42yo: June 11, 426^: Grasshopper Valley, 1880, Watson. 



* Saxifraga Rydbergii Small. 



Perennial, from short rootstocks, acaulescent. Leaves basal ; 

 blades oblong to ovate, 1-3 cm. long, undulate or repand-dentate, 

 glabrous or nearly so, bright green above, pale beneath, sessile, often 

 with a broad petiole-like base ; scapes solitary, erect, 5-10 cm. tall, 

 purplish, glandular-pubescent above, simple to the inflorescence ; 

 cymules contracted, accompanied by short bracts, disposed in an in- 

 terrupted cylindric raceme : calj'x glabrous, tube broadly campanu- 

 late or nearly flat at maturity, the segments 5, triangular, 1-1.3 mm. 

 long, rather obtuse ; petals 5, elliptic-oblong, shorter than the sepals, 

 fugacious, sessile : stamens 5 : filaments subulate ; follicles purple. 



The only close relative of Saxifraga Rydbergii is Saxfraga 

 hicracifolia W. & K. Selecting the more prominent characters that 

 separate the two species in question we may state them as follows : 



Saxifraga Rydbergii. — Leaf-blades sessile or wdth broad petiole- 

 like bases ; calj'x glabrous, the segments triangular, less than 1.5 mm. 

 long ; petals oblong-elliptic, shorter than the calyx-segments. 



Saxifraga hicracifolia. — Leaf-blades narrowed into long slender 

 petioles ; calyx pubescent, the segments ovate, 2 mm. long ; petals lin- 

 ear-oblong, as long as the calyx-segments. 



