This is the paperback edition of Lawton’s Moss Flora of the Pacific Northwest which was published in 1971. It is the first comprehensive moss flora of the Pacific Northwest (Washington, Oregon, Idaho, western Montana, Wyoming, and the Canadian Provinces of British Columbia and Alberta through the Rocky Mountains and north to about the fifty-second parallel). It contains complete descriptions, clear original illustrations, and keys to the 544 species and 54 varieties found in the region.