546 PROCEEDINGS OF THE ACADEMY OF [Oct., 



fimbriatula (S). (Serpentine form), Angelica villosa, Sabbedia angularis, 

 Asdepias verticillcda, Koelliei ffexuosa, Houstonia ccerulea, Lobelia spi- 

 cata. Eupatorium aromaticum, Solidago nemoralis. Aster ericoides, A. 

 parviceps pusillus, A. lateriflorus, Antennaria neglecta, A. plantagini- 

 folia, and Senecio bedsamita. 



Where the trees are somewhat closer together and over much of 

 the intervening area there is a shrubby growth forming dry upland 

 thicket. Salix tristis, Corylus americana, Rhus glabra, Ceanothus 

 americana, Gaylussacia baccata, ~\'accinium medians are predominant, 

 while frequent with these are Quercus diet folia. Q. prinoides, Rosa 

 hum ills, Rhus copallina, Xolisma ligustrina and Polycodium stamincum. 



Large areas of the open, and especially about depressions, are 

 covered with an abundant growth of greenbrier, mainly Smilax 

 rotundifolia, though accompanied by S. glauea. Juniperus virginiana 

 is the main tree of such depressions, and the densest growth of Smilax 

 usually occurs beneath it. Acer rubrum here becomes a tree of con- 

 siderable size. 



In the dry upland thicket and open woodland, and about the edge 

 of these cedar-greenbrier thickets, the vegetation is decidedly more 

 mesophytic, most of the species here being common to the surrounding 

 district. In the woodland occur PJiegopteris hexagonoptera, Panicum 

 dichotomum, P. boscii, L/inum virginianum, Dasystoma flava, Gerardia 

 tenuifolia, Hierdcium venosum, Nabalus serpentarius, Solidago bicolor 

 and Sericocarpus asteroides. Many other species of the surrounding- 

 flora are more or less casual here. 



In the greenbrier thicket and about its edge grow man}' herbs, 

 of which Andropogon furcatus, Seirpus atrovirens, Sdene steUata, 

 Vernonia noveboracensis, Eupatorium perfoliatum, Solidago rugosa, 

 Helianthus giganteus and Cirsium muticum may be mentioned as con- 

 stant and frequent. Beneath the dense shade of the cedars and 

 greenbrier and on banks of small streamlets PolysUchum aerosti- 

 choides, Asplenia m p'aty neuron, Homedocenchrus virginicus, Agrostis 

 perennans, Aretbis lyrata, Saxijraga virginiensis occur with other 

 species of the open dry barrens in ranker growth. 



Where depressions exist free from the covering of thicket or trees, 

 especially where, though not wet in summer, complete desiccation 

 seldom occurs, where the soil is largely a greenish sand, but not dry 

 or arid, a peculiar vegetation exists. Deschampsia ceespitosa and 

 Fimbristylis laxa occur here, with locally Cassia ehamaerista, Cyperus 

 aristatus, and Gerardia purpurea parvulu. 



Between the upland xerophytic woodland and the surrounding 



