304 E. G. LINSLEY 



floral provinces in the Far West. These represent the beginnings of 

 our modern floral and climatic provinces and undoubtedly had a 

 profound influence on the distribution and evolution of the present 

 fauna of cerambycid beetles. In his words: 



... a North-coastal province, extending along the coast from Washington 

 to central California, supported a relict warm-temperature facias of the 

 Arcto-Tertiary Geoflora. At the north it graded inland into the Columbia 

 Plateau province which was characterized by a typical temperate Arcto- 

 Tertiary Geoflora, and which gave way at higher levels and eastward to 

 a cool-temperate conifer facies. Near its southern margin the North-coast 

 province merged eastward into a floodplain facies of the Arcto-Tertiary 

 Geoflora which occupied central California, extending to the foothills of 

 the ancestral Sierra Nevada. On these better-drained slopes the floodplain 

 forest was replaced by vegetation representing an ecotone between the 

 Arcto-Tertiary and Madro-Tertiary Geofloras; owing to its near-coastal 

 position this ecotone included more humid types than that in west- 

 central Nevada. At higher levels in the Sierra, Madro-Tertiary species 

 were supplanted by the more mesic, temperate Arcto-Tertiary plants. 

 A South-coastal province, extending from coast-central into southern 

 California, was characterized by arid subtropical climate in which a 

 relict Neotropical-Tertiary Geoflora was in ecotone with the subhumid 

 Madro-Tertiary Geoflora. To the eastward, in the drier interior Mojave 

 province, the Madro-Tertiary Geoflora was dominant, grading northward 

 rapidly into an ecotone with the Arcto-Tertiary Geoflora in west-central 

 Nevada. 



MacGinitie has contributed to this symposium a vivid account of 

 the Tertiary climates of western North America. These have pro- 

 foundly influenced the distributional and phylogenetic histories of 

 the modern floras of western North America, including the redwood 

 forest, the black oak-madrone forest, the North Coast Douglas 

 fir forest, the upland conifer forest of the Sierra Nevada, and the 

 Rocky Mountain forest (Mason, 1947), which support large seg- 

 ments of the endemic cerambycid fauna. 



According to Axelrod (1948), most of the important trees and 

 shrubs now characterizing the Redwood, Sierra-Cascade, Rocky 

 Mountain, and North-coast conifer forests have close equivalents in 

 the West American Element of Miocene floras from the Columbia 

 Plateau and adjacent areas. These species are in such genera as 

 Abies, Acer, Alnus, Amelanchier, Betula, Castanopsis, Chamaecy- 

 paris, Corniis, Fraxinus, Gaultheria, Libocedrus, Lithocarpus, Ma- 

 honia, Rhododendron, Rosa, Salix, Sequoia, Sorbiis, Thuja, Tsuga, 



