33 2 
The Ohio Naturalist. 
[Vol. VIII, No. 6, 
ditions as would indicate a possible Ulmus-Acer zone as a succes¬ 
sor to the shrub zone providing other conditions do not prevent 
their development. However, if the trend of environmental 
conditions is to continue indefinitely as in the past there is little 
probability that this forest zone will be able to mature. 
The Cove Habitat. 
The Cove Habitat and its vegetation is one of the most 
marked ecological features of Cedar Point. The completeness 
of the vegetational structure and the size of the habitat, as exem¬ 
plified in Biemiller’s Cove and in other coves to the south of the 
Laboratory, are far in advance of anything in this line at Presque 
Isle and to say the least, the student of cove vegetation will find 
here exceptionally fine opportunities for such studies. Proceed¬ 
ing from the deepest water towards the shores the general struc¬ 
ture of the vegetation may be classified as follows: 
a. (The Chara Formation.) 
b. The Potamogeton Formation. 
c. The Castalia-Nymphaea Formation, 
d. The Phragmites-Typha Marsh Formation, 
e. The Ccilamagrostis canadensis Wet Meadow Formation, 
f. The Cephalanthus-Cornus Thicket Formation, 
g. The Rhus hirta Thicket Formation, 
h. The Ulmus-Acer Forest Formation. 
The Chara Formation. 
A few specimens of Chara were found at Piesque Isle in situa¬ 
tions similar to the Cove Habitat at Cedar Point and Pieters 
reports more or less complete Chara associations in the western 
end of Lake Erie and in Lake St. Clair, although seldom found 
where the bottom was sandy. ?1 Probably with proper facilities 
a search of the coves of Cedar Point would reveal a more or less 
well developed Chara formation; although generally sandy, the 
cove bottoms are not altogether so. 
The Potamogeton Formation. 
This formation is particularly well developed here and, in 
general, it very closely resembles the corresponding formation 
at Presque Isle. Its habitat may be said to comprise that part 
of the cove in which the water is four feet or more in depth, ex¬ 
cepting in the deepest portions where the Chara Formation may 
be more characteristic. The coves are likely nowhere so deep as 
to exclude the latter formation. The structure of the Potamoge¬ 
ton Formation is essentially as follows: 
21. Pieters, A. J. The Plants of Western Lake Erie with Observa¬ 
tions on their Distribution. U. S. Fish Commission, Bull. 1901 : 57-79. 
and The Plants of Lake St. Clair. Bull. No. 2, Michigan Fish Commission, 
1894. 
