Rydberg : Rocky Mountain flora 139 



petioles, which are slightly dilated and ciliate at the base ; blades 

 broadly lanceolate, 8-15 cm. long, usually more or less serrate 

 with ascending teeth, acute, glabrous or essentially so, hispidulous- 

 ciliolate on the margins, rather thick ; upper leaves lanceolate, 

 sessile or those of the inflorescence lance-linear ; inflorescence or 

 its few principal branches racemiform ; involucres 8-9 mm. high, 

 1 cm. broad ; bracts subulate, glabrous, with linear-lanceolate 

 green tips and green midveins below ; rays blue or bluish purple, 

 about 15 mm. long; disk-flowers red-purple; achenes glabrous, 

 at least in age. 



This may be the A. praecox of Hooker's Flora Boreali-Ameri- 

 cana ; but the name is preoccupied by A. praecox Willd. It is 

 related to A. Lindleyanus, but differs in the narrower leaves, of 

 which the lower are neither cordate nor broadly ovate and those 

 of the inflorescence are lance-linear, in the larger rays, which are 

 about 1 5 mm. long, and in the more ascending branches of the 

 simpler inflorescence. 



Alberta : Along streams, edge of woods on the Sulphur 

 Mountain, Aug. 16, 1899, McCalla 2026 (type, in herb. N. Y. 

 Bot. Gard.) ; roadside, Spray Avenue, Banff, Sept. 18, 1899, 

 McCalla 202 y ; below Wapta Lake, Aug. 6, 1904, /. Macoun 

 69480 ; gravelly banks, Second Lake, Rocky Mountain Park, 

 Aug. 3, 1 89 1, Macoun 7770. 



Aster Butleri sp. nov. 



Perennial, with a horizontal rootstock ; stem 4-10 dm. high, 

 glabrous, slender ; lower leaves petioled ; blades lanceolate, about 

 1 dm. long, distantly serrate with ascending teeth, hispidulous- 

 ciliolate on the margins, otherwise glabrous ; upper stem-leaves 

 sessile, narrowly lanceolate, or those of the inflorescence lance- 

 linear, entire ; inflorescence paniculate with numerous heads ; in- 

 volucres 5-6 mm. high, about 8 mm. wide ; bracts subulate, with 

 green midribs and narrowly lanceolate green tips, attenuate, gla- 

 brous ; rays bluish purple, 8-10 mm. long; achenes hispidulous- 

 strigose. 



This is related to the preceding, but differs from it in the large 

 inflorescence with numerous small heads, and in the pubescent 

 achenes. In the latter respect it differs from all the species of 

 the Aster Lindleyanus group. 



Montana: Gateway, Aug. 16, 1908, B. T. Butler 443 (type, 

 in herb. N. Y. Bot. Gard.) ; also 4JJ. 



