200 LEAFLETS. 



know what a completely distinct climatic region those coast 

 mountains have been constituted by nature. 



Erigeron hesperocallis. Large as E, callianthemus , 

 with equally showy heads, with broad purple rays, the pubes- 

 cence both of stem and leaf-margins more pronounced, the 

 leaves not only thinner and of a less pallid green, but more 

 narrowly lanceolate and instead of being obtuse, or barely 

 acutish, are attenuate-acute ; the bracts of the involucre are 

 more distinctly scaberulous and less viscid, the achenes are 

 shorter and broader, the pappus of more delicate bristles ; last 

 and not least of the differences being that herbage readily fer- 

 ments and darkens in the drying, while the firmer and glau- 

 cescent E. callianthemus undergoes no such change. 



The best specimens of E. hesperocallis before me are of my 

 own collecting on Mount Rainier, 20 Aug., 1889. The plant 

 grew copiously in a woodland opening with a marsh in the 

 midst and a stream flowing through from the lake which is 

 near the limit of trees on the west side. Both Mr. Howell 

 and Mr, Suksdorf have often distributed the same plant, in 

 less luxuriant form, from Mt. Hood in Oregon, and Mt. Adams 

 in Washington. Mr. Gorman collected it in a smaller form at 

 Crater Lake, on Mt. Pitt, in southern Oregon ; this plant, 

 however, departs from the type in having its basal leaves 

 obtuse, also with a more or less hairy midvein. Again, and 

 far away in northwestern Washington, in the Olympic Moun- 

 tains, Mr. A. D. E. Elmer (n. 2623) obtained a form, or ally, 

 of the present species with leaves basal and cauline equally 

 narrow and acute, and glabrous except as to a rather conspic- 

 uous white- villous ciliation. Yet again, in the Wenatchee 

 Mountains, away in the northern interior of the same State, 

 the same Mr. Elmer has (n. 447) another ally with the nor- 

 mally very acute, and in drying blackened foliage, but the whole 

 herbage cinereous with a fine soft pubescence. Future ex- 

 ploration of the vast Northwest, on both sides of the British 

 boundary, will be likely to form my E. hesperocallis as here 

 circumscribed an aggregate. 



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