HERBACEOUS FLORA OF FORESTS AND FIELDS. 63 



pubescent beneath, the berries in compact rather oval clusters, pur- 

 plish black without bloom, juicy, and sweet, ripening in the latter 

 part of September. Rohlnia hkpida and Rosa hum.ilis are common 

 on these rocks. Amorjjha virgata and Vilmrnum acerlfolium prefer 

 slight declivities with a dry but somewhat less rocky soil. Among 

 the other xerophile rupestrian associations, on the summit of Che- 

 hawhaw Mountain rock-tripe, a large lichen (Umbilicaria), covers 

 with its black thalloid frond the bare crags, and forms a striking 

 feature; it has also been observed to cover the rocks on the crest of 

 Lookout Mountain (De Kalb County, 1,800 to 2,000 feet altitude), 

 and is characteristic of the southeastern Alleghany ranges north to 

 Pennsylvania. Of the few ferns frequenting these arid heights, 

 Chellanthes tomentom is the most common. The long stipes of the 

 fronds lie deeply buried among the smaller fragments of the rocks, 

 where the fibrous roots, protected from the sun, find the needed 

 supply of moisture. Dry(ypteris marginalis is rarely found in the 

 sheltered rocky clefts. The coarse Andropogoneae, already named, 

 under the scanty shade of mountain oaks, chestnuts, and pignut hick- 

 orj', completelv hide the ground with their luxuriant growth. The 

 fine tufts of StenophyUus capiUaris^ with Talimim teretifolkmi^ cover 

 the fiat expanses of the rocks, bare of any other vegetation. Silene 

 stellata and Anychia dicJiotoma prefer the shaded rocky shelves. Stei- 

 ronema toyisum^ through the abundance of its bright golden flowers, 

 is the most conspicuous among the herbs. This ornament of the cliffs, 

 extending northward to the mountains of Kentuck}^, has also been 

 observed on the open hills of the Delta divide (Clay County, altitude 

 1,600 feet). Laclnaria graininifolla^ in dense tufts formed b}" its 

 confluent tuberous root-stocks, covers the sunny rocks throughout this 

 subdivision, while the following, more or less common throughout the 

 southern extent of the Appalachian chain, are frequenth^ met with in 

 open rocky woodlands: 



Campanula diniricuta. SoUdago ererta. 



Dasy stoma flava. Brachychai'ta sjyharelata. 



Solidago hicolor. Gerardia ieutiifolia asprrida. 



Wherever the ridges spread out into wider expansions forming 

 broad uplands, now denuded of their original forest growth and mostl}^ 

 subjected to cultivation, a xerophile campestrian flora has taken pos- 

 session, with Compositae as its prominent feature. Such plains extend 

 through the metamorphic region of South Carolina and Georgia to 

 its southern limit in Alabama, with an elevation of from 1,<)00 feet 

 (Clay County, about Delta) and 1,200 feet (Cleburne County, Chula- 

 finnee) down to 860 feet in Lee County (Auburn). The borders of 

 fields and woods, meadows and pastures, appear to be emphatically 



