XEROPHILE AND MESOPHILE HERBACEOUS VEGETATION. 73 



the former, many ferns peculiar to the mountain region take root in 

 the chinks of the bare rocks. Such are: 



Cheilanthes tomentosa. Asplenium montanum. 



Cheilanthes lanosa. Asplenium ruta-muraria. 



Cheilanthes alabamensis. Asplenium, pinnatifidum. 

 Pellaea atropurpurea. 



In similar situations are found the following flowering plants: 



Silene rotundifolia. Arenaria stricta. 



Silene caroliniana. Ladnaria graminifolia. 



Saxifraga virginica. Senedo obovatus. 



Other species of ferns on the border line of xerophile and meso- 

 phile associations prefer the more sheltered rocky ledges, as: 



Asplenium parvulum. Dicksonia punctilobula. 



Woodsia obtusa. Camptosorus rhizophyllus. 



Polypodium vulgar -e. Cytstopteris fragilis. 



Carex picta (C. boottiana) covers in dense tufts the rocky shelves on 

 the banks of the head waters of the eastern Sipsey fork, in Winston 

 County, where this pretty and rare plant was collected by the late 

 Judge T. M. Peters. 



Associated with Carex picta are C. nigro-marginata, C. virescens, 

 and C. digitalis, Tipularia unifolia (of a widely disrupted distri- 

 bution from the Gulf coast to Lake Huron in the Alleghenian area), 

 and the northern Perami/um ( Goodyera) repens. Therofon (BoyMnia) 

 aconitifolium inhabits the bare rocks forming the brink of streams, 

 and Diarnorpha pusilla is found in similar localities both extend- 

 ing hither from the lower mountains of South Carolina and 

 Georgia. Heuchera americana grows in more open, and H. rugelii, 

 Viola multicaulis, and Hepatica hepatica in deeply shaded situations; 

 and where the rocky walls are constantly kept moist by the dripping 

 water, Thalictrum clavatum, Viola rostrata, V. blanda, and V. striata 

 are found. 



In the open woods of a light dry soil where pines are mingled with 

 the hardwood trees, and in the openings of old fields and pastures, 

 where the progeny of the pine is apt to take possession of the ground, 

 there are present numerous xerophile species, which are character- 

 istic of the mountain region in general. Of these, the following glu- 

 maceous plants (grasses and sedges Poaceae and Cyperaceae) are 

 scantily diffused throughout woods and fields having a thin thirsty soil: 



Erianthus alopecuroides. Eragrost'is pectinacea. l 



Andropogon scoparius. l Poa chapmaniana. l 



Andropogon furcatus. l Carex laxiftora. l 



Chrysopogon avenaceus. * Carex laxiflora varians. l 



Sieglingia seslerioides. l Carex cephalophora. 



Melica mutica. l Carex leavenworthii. 



Occurs also in the Louisianian area. 



