208 BOTANICAL GAZETTE [MARCH 
while the lower parts are dominated by elm. In the area between 
quadrats 59 and 96 and vicinity (fig. 1), which is the lowest part 
of the woods, there are almost no trees except elms. I shall 
frequently refer to that part of the woods that is dominated by 
maple as the maple consociation, and that dominated by elm as 
the elm consociation. 
The great majority of the shrubs are of two species, Asimina 
triloba and Benzoin melissaefolium. Both of these are very abun- 
dant, and are distributed throughout the forest except in the highest 
and lowest parts. No other shrubs are abundant except the species 
of Crataegus, which occur mostly along the border. 
The subdominants of the herbaceous layer vary with the season 
as well as with the location within the forest. In the prevernal 
season Claytonia virginica, Isopyrum biternatum, and Collinsia 
verna often form extensive and conspicuous societies in the maple 
consociation. The two species of Dicenira, D. cucullaria and 
D. canadense, occur together as subdominants in a rather extensive 
prevernal society. Phlox divaricata and Geranium maculatum form 
less extensive but not less well marked societies. Asarum canadense 
is everywhere abundant, but because of its growth habit is not 
conspicuous. Viola sororia is abundant, but is scattered too much 
to be considered a subdominant. In the elm consociation Floerkia 
proserpinacoides forms an extensive and extremely dense society. 
Like the elm this plant is present throughout the forest, but is 
always thickest where the elms are dominant. 
During the vernal season Hydrophyllum appendiculatum forms 
an extensive society in the maple consociation. Later H. canadense 
is a subdominant over less extensive but more closely occupied 
areas. Cystopteris fragilis is abundant over considerable areas, and 
locally is present in such numbers as to become a subdominant. 
Podophyllum is also common, but as usual forms local colonies 
rather than extensive societies. All of these societies extend into 
the elm consociation, but there is no subdominant that is charac- 
teristic of the elm consociation during this season. 
The aestival season is characterized by the subdominance of 
Laportea canadensis over great areas. Like the dominant shrubs 
Asimina and Benzoin, the wood nettle is abundant throughout 
