44 Proceedings of the Ohio State Academy of Science. 



(Fig. 15.) This indicates submergence due to settling of the 

 peat. At low water the exposed peat bench quickly becomes 

 covered with land plants. The extreme fluctuation in water 

 level, 5-8 feet at times, 6.85 feet below the normal water level 

 during the winter of 1909, has destroyed or at least greatly dis- 

 turbed the fixed aquatics. 



Fig. 15. — Masses of dead Rhus, Acer and Alnus at low water in a large 

 lagoon on the east side of Cranberry Island. 



III. Vegetation of the shore. 



A typical reed association, frequently the bordering zone of 

 bogs, marshes and swamps, and well developed in other portions 

 of the lake, is here but imperfectly formed. Typha latifolia is 

 present in considerable numbers. The relative position of these 

 species in the association, especially with reference to the depth 

 of water, is also subject to variation ; so it seems to me, that 

 here, rather than a zonation of swamp societies is an 



