Summary

Do the plants that are common to Europe and North America nearly all live north of the Arctic Circle? CD bases his question on HCW’s "capital" comparison between relations of Europe to North America and Europe to E. Asia if the intervening land had been submerged. CD has been led to speculate that in the mid-Pliocene the organisms now living in middle Europe and northern U. S. lived within the Arctic Circle. Subsequent movements of this flora with advance and retreat of glaciers would explain present distribution better than Forbes’s vast submergences.