43 



The next well-marked coastal plain center seems to be in the 

 southern corner of North Carolina. The following species are 

 rarely, if ever, seen more than lOO miles from Wilmington : 



Tofieldia glabra, Hypoxis niicrantha, Dionaea imiscipiila, Kalinia 

 aineata, Coreopsis falcata, Leptopoda Cnrtisii. 



The following species of wider distribution seem to be more 

 abundant within about 50 miles of Wilmington than they are at 

 a distance of 100 to 200 miles in either direction : 



Selaginella acanthonota, Pinus pahistris, P. scrotina, Aristida 

 stricta, Campidosiis aromatiais, Dichromena latifolia, Zygademts 

 gladerriiniis, LUiuin Catesbaei, SmUax laiirifolia, Habenaria blc- 

 phariglottis, Nyuiphaca sagittifolia, AmorpJia herbacea, Poly gala 

 hitea, P. ramosa, Gordo nia L asiaiitlnis, Cyrdla raccmiflora, Clethra 

 aluifolia, Vaccinuim crassifoliiim, Sabbatia lanceolata, Carphe- 

 pJioriis bellidif alius. Aster sqnarrosus, Marshallia graininifolia. 



By far the greatest center of pine-barren plants, or perhaps 

 an aggregation of two or more subcenters, is in Georgia and 

 northern Florida. Probably | if not -^^ of all pine-barren spe- 

 cies can be found in Georgia ; at least a dozen are confined to 

 that state and many more to Georgia and Florida together. In 

 the Altamaha Grit region (the middle third of the coastal plain) 

 of Georgia there are nearly 150 species on sand-hills, about the 

 same in dry pine-barrens, 200 in moist pine-barrens, and 75 in 

 pine-barren ponds. These numbers are undoubtedly larger than 

 for the same habitats in any other state unless it be Florida. 



In subtropical Florida there are of course many plants not 

 found farther north, but practically all of these center in the 

 tropics and therefore outside of the region under consideration. 



Going westward from Florida we find in the vicinity of Mo- 

 bile and Pensacola a center comparable with that in southern 

 North Carolina. To this belong Myrica inodora, Sarracenia 

 Driimmondii, Drosera filiformis Tracyi, Pitcheria galactioides, and 

 perhaps Carphephorus Pseiido-Liatris. CJiamaecyparis thyoides 

 and Sarracenia purpurea, which are as common within 50 miles 

 of Mobile Bay as they are in New England, seem to be entirely 

 wanting at twice that distance, and do not appear again within 

 two or three hundred miles, as far as known. 



