ROOTED AQUATIC PLANTS IN LIMNOLOGY 



117 



A study of the tables published by Fas- in the soft clear water lakes and in bog 



sett and by Steenis sliow that species of lakes. Species of the third type may oe- 



the first type are most abnndaiit in those cnr in all fresh waters. Species of the 



lakes of medium hard, or hard water. Spe- fourth type occur almost exclusively in the 



cies of the second type are most abundant medium and hard-water lakes. The spe- 



FlG. 11. Diagrams showing stages in tlie succession of aquatic plants in seepage lakes of Xortheru 



Wisconsin. See text for discussion. 



