3o6 



The Ohio Naturalist. 



[Vol. VIII, No. 6, 



The facies exhibit a distinct alternation in the Typha-Scirpus 

 Formation. On the wet bank, and extending out into the water 

 to a variable depth of about a foot, is the Scirpus americanus 

 Consocies, alternating here and there with the Typha lati folia 

 Consocies, while beginning in 6 or 8 inches of water and extending 

 out into the deeper water of the lagoon, is the Scirpus validus 

 Consocies, the latter thus forming a zone in the deeper part of 

 the habitat. In this consocies Castalia is beginning to appear 

 in a few places in the deepest part and, providing the marsh 

 formation does not build up the soil and advance too rapidly, 

 there may soon be initiated a new formation between the Typha- 

 Scirpus Formation and the Potamogeton Formation. 



In the upper part of the Typha-Scirpus Formation, and 

 extending up to the outer Populus-Salix Formation, there is a 

 zone the status of which was not satisfactorily determined. This 

 zone has been provisionall}^ designated as follows: 



Fig. 4. Looking east across the new lagoon a few rods south of the 

 Break-water. Typha-Scirpus Formation conspicuous. Lake in distance 

 and bar visible just beyond the marsh vegetation. Young cottonwoods 

 and willows in immediate foreground are submerged by unusually high 

 water. 



The Salix (spp.) Formation. 



This structure probably represents a transitional condition 

 the true status of which will become evident in the future. At 

 present it consists of several species of Salix with scattering 

 individuals of Vitis vulpina, Bidens frondosa, Polygonum penn- 

 sylvanicum. Ambrosia trifida, etc. The structure is evidently 

 the beginning of a thicket formation similar in position to the 

 Myrica-Salix thicket formation on Presque Isle. 



