LILIES OF THE WESTERN UNITED STATES & BRITISH COLUMBIA. 351 



THE LILIES OF THE WESTERN UNITED STATES AND 



BRITISH COLUMBIA. 



By Cakl Purdy, U.S.A. 



Thirteen clearly distinct species of Lilies have been found in the region 

 indicated by my title and lying west of the Rocky Mountains. 



Along the coast of California and Oregon there is a broad moun- 

 tainous belt, from fifty to eighty miles wide, called collectively the Coast 

 Range. 



With its plateaus facing the ocean, its valleys and vales, its low hilly 

 regions, and great mountains rising to six thousand feet altitude, with 

 forested areas of varied character throughout its extent, and hundreds of 

 climates, it is a great and wonderfully diversified region. 



Parallel with the Coast Range, separated from it by the broad valleys 

 of California and Oregon, and by the sound farther north, connected to 

 it by several great cross ranges greatly exceeding it in altitude, differing 

 greatly in soils and far less humid, is another great system called in 

 Southern California the Cuyamaca and San Bernardino Mountains, in 

 Central and Northern California the Sierra Nevadas, and in Oregon and 

 Washington the Cascades, and which collectively can be called the Sierra 

 Nevada mountain system, and, under whatever name, forming part of 

 the great barrier between the fertile Pacific slope and the arid regions of 

 the great central plateau. 



To these two great mountain systems nine of our Lilies are confined. 

 Lilium columbiamim continues east over the upper Columbia River 

 basin, L. Parryii is found also in the high mountains of Arizona, 

 and L. Boezlii and L. ijardalinum are doubtfully reported, the one from 

 Utah in the Great Basin, the other from the shores of Lake Winnipeg, 

 far east of the Rocky Mountains. 



To the Sierra Nevada system of California six species belong, 

 three of them peculiar to it. To the Coast range of California, 

 from San Francisco Bay north, a length of 250 miles, seven of 

 our thirteen species are native, five its exclusive property. Oregon 

 has four species, only one peculiar to it, while north of the Columbia 

 River only L. ijardalinam and L. coluinhianum extend into British 

 Columbia. 



From the Sierra Nevada system east to the Rocky Mountains lies a 

 vast region, treeless in its lower levels, desert or arid in its middle and 

 southerly extent. Out of these arid lower levels great mountains rise 

 here and there, the islands of an ancient sea. This great arid break 

 separates the Lilies of the Pacific slope from their Atlantic cousins, and 

 in it no Lilies have been found. 



The thirteen Pacific coast species can be divided by their affinities 

 into three groups. 



In the first we should find L. coliimhianam and L. Humboldtii, 



