Professor Wallace in his delightful _Island Life_ as well as otherwriters in many important works, have put forward ingenious hypothesesto account for the identity of flora and fauna on widely separatedlands, and for their transit across the ocean, but all areunconvincing, and all break down at different points.It is well known that wheat as we know it has never existed in a trulywild state, nor is there any evidence tracing its descent from fossilspecies. Five varieties of wheat were _already cultivated_ in Europein the stone age--one variety found in the "Lake dwellings" beingknown as Egyptian wheat, from which Darwin argues that the Lakedwellers "either still kept up commercial intercourse with somesouthern people, or had originally proceeded as colonists from thesouth." He concludes that wheat, barley, oats, etc., are descendedfrom various _species now extinct_, or so widely different as toescape identification in which case he says: "Man must havecultivated cereals from an enormously remote period." The regionswhere these extinct species flourished, and the civilization underwhich they were cultivated by intelligent selection, are both suppliedby the lost continent whose colonists carried them east and west.