33° 
The Ohio Naturalist. 
[Vol. VIII, No. 6, 
facies alone, the Typha latifolia Consocies being found in the 
deeper water and in perhaps more exposed positions than is the 
Phragmites phragmites Consocies. 
The immense accumulation of muck underlying this marsh is 
likely the product of the accumulation and subsequent more or 
less complete humification of the remains of the plants of this 
formation. The annual growth of these plants constitutes a large 
quantity of vegetable matter which, upon its death, is placed in 
most favorable condidons for its retention and subsequent 
humification. In places where the accumulation of humus has 
been so rapid as to raise the level of the soil above the water or, 
as along the edge of the Bar Section, where sand drifts in and 
helps to build up the soil, there follows a succession by either the 
Calamagrostis canadensis Wet Meadow Formation or by the 
Salix discolor-lucida Thicket Formation. 
Fig. 16. The Black Channel and the Pliragmites-Typha Marsh For¬ 
mation. The forests in the far distance are at the edge of the mainland 
on the other border of the marsh more than two miles distant. 
The Salix discolor-lucida Thicket Formation. 
There are no very well marked examples of this formation and 
its structure is not clear to the writer. However, the structure 
has been correlated with a similar and well-marked formation at 
Presque Isle, and in the limited areas where it occurs along the 
Bar Section it agrees well with the Presque Isle formation. It 
possibly may prove to be the same structure as was called the 
