VEGETATION OF ROCK HOUSES. 75 
The following are frequent in the openings of woods and on their 
borders: 
Vagnera racemosa. Tiarella cordifolia. 
Uvularia puberula. Hypericum virgatum. 
Uvularia sessilifolia. Scutellaria incana. 
Iris cristata. Phiox divaricata.' 
Syndesmon thalictroides. Mertensia virginica. 
Anemone quinquefolia. Vincetoxicum hirsutum. 
Anemone virginica. Gentiana villosa.) 
Ranunculus recurvatus. Galium circaezans. 
Cimicifuga racemosa. Houstonia caerulea. 
Trautvetteria carolinensis. Deringa canadensis. 
Viola hastata. Podophyllum peltatum.! 
Viola multicautlis. Sanguinaria canadensis. 
Viola pubescens. 
On the higher shady banks of water courses are found: 
Porteranthus (Gillenia) stipulaceus. Stachys cordata. 
Porteranthus trifoliatus. Zanthorhiza apiifolia.' 
In the more or less dense forest, covering hill and dale, are to be 
found: 
Orchis spectabilis. Aralia racemosa. 
Cypripedium parviflorum.' Sanicula marilandica (rare). 
Arisaema quinatum. Phryma leptostachya. 
Circaea lutetiana. Frasera carolinensis." 
Hydrastis canadensis! (scarce) . Cynoglossum virginicum. 
Bicuculla cucullaria. Obolaria virginica. 
Dentaria diphylla. Solidago flexicautis. 
Cubeliwm concolor. Solidago vaseyi. 
Panax quinquefolium:' 
The Solidago vaseyi has been collected near Holmes Gap (1,500 
feet), and is known from a few localities on the highest ranges of the 
Carolinas and Georgia. 
On the restricted flat semiswampy places, not infrequently met with 
on the Warrior table-land, open or slightly under cover, the following 
are most frequently seen: 
Cyperus pseudo-vegetus.! Phlox maculata. . 
Carex lupulina.} Lysimachia quadrifolia. 
Carex lurida.} Gentiana elliottii. 
Habenaria ciliaris.* Bidens involucrata. 
Xyris fleruosa.) Coreopsis grandiflora. 
Rhexia virginica. Doellingeria infirma. 
Ludwigia alternifolia. 
Mesophile plant associations of rock howses.—On the perpendicular 
walls at the head of the deep narrow gorges are found shelves of hard, 
resisting sandstone with the softer strata beneath them worn away by 
the action of the percolating surface water. The wide and deep exca- 
1 Occurs also in the Louisianian area. 
