206 Part III. Chapter. 3. 
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120 10 100  W.E.Greemr. 
Fig. 4. Map illustrating original Centers of Plant Dispersal as determined by 
the glacial Conditions of the Continent. 
A Arrows illustrate directions of glacial and post. glacial Plant Migration. KEZZZ Kansın 
Stage of Glacier. In EB Mlinoian Stage of ice FERRERNT, ı& Jowan Stage. _BS_ Southern 
limit Wisconsin Stage. Boreal Flora along front of Terminal Moraine. TR Dispersal 
Center of Deciduous Vegetation. Bw] Dispersal Center of Coniferous Forests of Pacific Coast. 
PVe4 Dispersal Center of Prairie Vegetation. Dispersal Center of Desert Vegetation. 
Dispersal Center of Tropie Vegetation. 4-7 Pleistocene Bridge. 
