ECOLOGICAL STUDY OF BRUSH LAKE. l6l 



present to obtain the transition from the lake shore forest to the 

 culmination forest of the region. For this reason the normal 

 upland forest will not be considered here. The typical trees are : 



Acer saccharinum L,. Salix nigra Marsh. 



Fraxinus americana L- " amygdaloides And. 



" pennsylvanica Marsh. " discolor Muhl. 

 Ulmus americana L. 



All of these are reproducing well and advancing inward upon 

 the shrub zone. 



In the drier, outer parts of the forest zone are also found the 

 following trees : 



Gleditsia triacanthos L. Prunus americana Marsh. 



Populus deltoides Marsh. Cornus florida L. 



Morus rubra L. Rhus glabra Iy. 



Viburnum prunifolium L. Juglans nigra L. 



Viburnum lentago L. Ouercus macrocarpa Mx. 



There are comparatively few shrubs in the typical swamp 

 forest. The following were collected : 



Cornus amomum Mill. Opulaster opulifolius (Iy. ) Ktz. 



Sambucus canadensis L. Rubus occidentalis L. 



Viburnum opulus L. 



In the drier parts the three lianas given below are quite 

 abundant : 



Rhus radicans L. 



Parthenocissus quinquefolia (L. ) Planch. 



Vitis vulpina L. 



In the outer, drier portions of the forest zone herbs are quite 

 numerous. This is probably due to the changed and still chang- 

 ing conditions, as a considerable number would probably be 

 absent if conditions were normal as formerly, when the hydro- 

 phytic forest was continuous with the vast mesophytic forest of 

 the region. Probably most of the herbs present were collected, 

 and the following is the complete list of species, none of which is 

 especially prominent over others in the society : 



Equisetum arvense L. Cinna arundinacea L. 



Arisaema triphyllum (L ) Torr. Poa pratensis L. 



Spathyema foetida (L.) Raf. Elymus striatus Willd. 

 Panicum capillare L. " virginicus L. 



Muhlenbergia mexicana (L.) Trin. " canadensis L. 



