April, 1908.] 
The Vegetation of Cedar Point. 
3 2 
Secondary Species: 
Gleditsia triacanthos , 
Parthenocissus quinquefolia, 
Juniperus virginiana, 
Quercus velutina, 
Panicum virgatum, 
Andropogon scoparius, 
Elymus striatus, 
Asclepias syriaca, 
Toxicodendron pubescens, 
Celastrus scandens, 
Prunus serotina, 
Amelanchier sp., 
Vitis vulpina, 
Artemisia caudata, 
Rubus nigrobaccus , 
The various dunes scattered about in this section of the 
peninsula exhibit considerable alternation as to the facies so 
that there may be distinguished the Prunus virginiana Con- 
socies, the Rhus aromatica Consocies, and the Ptelea trifoliata 
Consocies. These three structures are, however, often mixed 
indiscriminately on the same dune. 
Fig. 9. The Dune Section, looking southwards from the Lake Labora¬ 
tory. To the left are the dunes and blowouts, between which and the 
Bay to the right is the forest strip, here mainly consisting of the Ulmus- 
Acer and Ailanthus formations. (Photograph by Prof. Herbert Osborn.) 
One of the most noteworthy peculiarities of this vegetation 
is the relatively large percentage of lianas and it is, in many cases, 
due more to the presence of these plants than to the other vege¬ 
tation that the integrity of the dune is preserved against the 
vigorous action of the wind. In fact it appears that many of the 
dunes were initiated by the lianas or at least held by them until 
the invasion of the shrubs was accomplished. Especially notice¬ 
able in this connection are Vitis vulpina and Parthenocissus 
quinquefolia. 
