1910 copyright; J.K. Gill Company publishers, Portland, Oregon; hardbound in heavy-weight paper; very good condition with unmarked pages.
 
Description -
States he will find the Wasatch Mountains as part of the eastern boundary of Idaho, and if he is familiar with the mammalian life of the Eocene period, he will remember that Professor Marsh and others have described a wonderful and varied fauna of large mammals which lived on the borders of an old lake east of the Wasatch Mountains. In fact the mountains themselves formed the lofty western shore line of that Eocene lake. But of all this abundant life, not one well identified fossil mammal has been found in Oregon belonging to that Eocene epoch. The author of The Two Islands reasoned that the Oregon land must have been cut off from the Wasatch land by an intervening body of water.