59 



Two or three other theories readily suggest themselves. 



P^irst, it might be supposed that the original home of this tree 

 was among the mountains, before the coastal plain assumed its 

 present form or became adapted to the growth of this species. 

 But the fact that it is so much more abundant and widely dis- 

 tributed in the coastal plain than in the mountains makes this 

 supposition improbable. 



Again, it will be noticed that it is just in this longitude (85 °W,) 

 that the fall-line (cast of the Mississippi) bends farthest south, and 

 it is possible that the climate or some combination of causes has 

 created a tension in the range of Pi)iiis palustris sufficient to 

 cause it to break through the barrier '^ here and overflow, as it 

 were, into the Piedmont region and mountains beyond for a dis- 

 tance of over 100 miles. As the limit of its distribution in this 

 region does not coincide w'th any known geological or climatic 

 line, it is not unlikely that its range was restricted only by the 

 time elapsed since it broke through the fall-line, and it may have 

 been still spreading at the time civilized man appeared on the 

 scene and stopped it. 



Another possible explanation is this. In most of the counties 

 from Floyd southward to the fall-line there are frequently found, 

 mostly near streams, considerable areas of unconsolidated deposits 

 believed to be of Pleistocene age, lying unconformably on the 

 older rocks. These indicate that much of this land was sub- 

 merged beneath the sea in comparatively recent geological times, 

 probably not antedating the appearance of most of our living 

 species of trees. Perhaps Finns palustris and several other species 

 which have a similarly anomalous distribution {e. g., Qucrcus 

 lyrata, Q. MicJiauxii, Magnolia glauca, flex glal)ra,'\ Nyssa tini- 

 flora), retreating before the advance of the Pleistocene sea, found 

 congenial homes among these highlands, with soil suited to their 

 needs, and have therefore remained ever since. 



Notwithstanding the abundance of long-leaf pine in the region 

 under consideration, it seems to be very little used for lumber, 

 and not at all for turpentine. A part of the charcoal which is 



*See Bull. Torrey Club, 31 : 10. i',04. 

 tSeeC. L. r>oyntoii, Hiltmore Hot. .^tud. i: 144. 1902. 



