WESTERN SPECIES OF ARABIS. 73 



in certain species which verge toward the A. platysperma 

 group. Their flowers are apt to be larger than in other and 

 taller species, and are perhaps always of a deep red-purple, 

 not so very unlike those of the ^. Breweri group. Their pods 

 are many, and are usually almost horizontally spreading and 

 secund ; in this particular most unlike A . Breweri. 



Arabis oreocalus. Low subalpine multicipitous peren- 

 nial, the partly hypogeous branches of the caudex short, stout, 

 covered below the living foliage by the imbricated persistent 

 bases of the leaves of former seasons, the whole plant 4 or 5 

 inches high and grayish : basal leaves Y^ inch long or more, 

 the obovate acute entire blade tapering abruptly to a broad 

 petiole of its own length, both faces minutely and not very 

 densely stellate ; cauline leaves uncommonly many and well 

 developed, approximate, large for the plant, spatulate-obovate 

 to oval and narrower, sessile, obscurely auricled, greener than 

 the basal, only sparingly stellate : raceme in flower short and 

 corymbiform ; sepals purplish-green and with few or no stel- 

 late hairs, always with a narrow purple-scarious margin ; 

 petals broad, obtuse, of a rich purple : pods (immature) few, 

 short, narrow. 



Collected in the Selkirk and Rocky Mountains, B. C, at 

 7,000 feet, by C. H. Shaw, July, 1904. 



Arabis bracteolata. Multicipitous dwarf 3 or 4 inches 

 high, the basal leaves in small rosettes, with distinctions of 

 obovate or oval blade and broad petiole not strongly marked, 

 the leaf as a whole only K to >^ inch long, densely and can- 

 escently stellate : flowering stems slender, their leaves sessile 

 and in the form of ovate-sagittate bracts less than Ji inch long, 

 glabrous, glaucous : flowers unknown : pods only 2 to 4, about 

 1 inch long, a line wide, obtuse, slightly arcuate and spread- 

 ing, the valves thin, nerveless : seeds in 1 row, rather thick, 

 short-oval, not winged, though with traces of a narrow scar- 

 ious margin. 



