XEROPHILE HERBACEOUS PLANTS AND MESOPHILE FORESTS. 83 
near Moulton, the following prefer the slightly sheltered rocky 
shelves: 
Allionia nyctaginea. Lithospermum canescens. 
Ranunculus fascicularis. Lithospermum tuberosum. 
Arabis laevigata. Salvia urticaefolia.' 
Claytonia virginica. Scutellaria cainpestris. 
Arenaria serpyllifolia, Polymiia canadensis radiata, 
Opuntia rafinesquii.' Bellis integrifolia. 
Geranium maculatum.! 
Sedum pulchellum and Phacelia pursh/i adorn the interstices of the 
rocky fragments, and Arenaria putula the bare rocks. During the 
first summer months the golden flowers of (Zyper/eum aureum and FH. 
sphacrocarpon' adorn the hills, giving way in the latter part of the 
season to blue and purple asters— Aster oblongifolius,' A. laevis lati- 
folius, A, cordifolius and others of the more commonly diffused 
species—and to the bright flowers of goldenrods, such as Solidago 
amplexicaulis and Brachychacta sphaccdata (B. cordata Vorr, & Gr.), 
which are confined to the lower southern Appalachian ranges. 
West of the spurs of the Cumberland highlands isolated knolls rise 
above the wide river plain with its seemingly interminable fields of 
cotton, corn, and small grain. These hillocks, of a siliceous limestone 
which has resisted erosion, support with their scanty covering of soil 
a stunted growth of chinquapin oak (Quercus acuminata), wild plum 
(Prunus americana), honey locust ((/ed/tsia triacanthos), hop hornbeam 
(Ostrya virginiana), and shrubs common on dry calcareous soil, and are 
frequently destitute of large trees. The plants which find a refuge in 
these localities form an interesting combination of xerophile, campes- 
trian, and sylvan associations. Under the shades of the denser clumps 
of the low trees have been noted: 
Poa sp. Dentaria laciniata, 
Leptorchis liliifolia. Methomia pauciflora, 
Cypripedium parviflorum. Mertensia virginica. 
Delphinium tricorne. 
In exposed places the following species of the open plain have estab- 
lished themselves: 
Arenaria patula. Euphorbia obtusata (rare). 
Tsanthus brachiatus. Kuhnistera gattingeri. 
Anemone caroliniana. Grinidelia lanceolata. 
Hypericum prolificum (frequent) . Amphiacharys dracunculoides. 
The Kuhnistera is rendered attractive by its numerous spikes of 
rose-purple flowers. The last two are remarkable outposts, if not waifs, 
from the plains west of the Mississippi River. 
Mesophile forests. —North of the Tennessee River the detached spurs 
of the Cumberland Mountains, capped with the sandstones and con- 
1Extends to the Louisianian area. 
