1905] TRANSEAUBOGS OF THE HURON RIVER VALLEY 



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green, yellow, and red, depending upon the season of the year. 

 Where the moss is disturbed by the uprooting of plants, the substra- 

 tum becomes exceedingly dry. The moss dies out, and in place of 

 it there springs up a growth of Cladonia rangiferina, C. pyxidata, 



FIG. ii. Chelsea bog. 



C. gracilis, C. verticillata, C. cristatella, and frequently a small 

 admixture of Rumex Acetosella. These plants gradually close over 

 the surface and aid in the conservation of the moisture. As the 

 conditions become more favorable, the Polytrichum again closes over 

 the area, driving out the lichens. About the borders of the shrubs 



