INTRODUCTION 



southern isolation strongly favors the statement made above that 

 most of the pine-barren flora was of southern extraction, for it is 

 quite reasonable that the species found on the Tennessee moun- 

 tains and in the pine-barrens of New Jersey are simply relicts of 

 an ancient American southern flora that must, at one time, have 

 covered a vastly greater area than it does today. The present 

 nearly complete isolation and the post-glacial distribution of this 

 southern flora, both it seems to me, favor this view. 



41. There remains still to be considered the "pine-barren" 

 plants of Long Island and Staten Island, not to mention regions 

 further east. As Stone has shown, a good many of these alleged 

 "pine-barren" plants are only coastal plain plants,* which are 

 found, it is true, in the pine-barrens; but more commonly in the 

 area surrounding them, frequently throughout the Atlantic sea- 

 board from Massachusetts to Florida. It should be remembered 

 in this connection that neither Long Island nor Staten Island are 

 in the same geological category as Beacon Hill. For both the 

 former were in part covered by the glacier and both were more or 

 less within the influence of glacial activity. f It is, of course, a 

 matter of pure speculation whether any vegetation persisted on 

 Long Island during the Pleistocene or not, but the evidence, except 

 for a few minor exceptions, seems to point to a negative probability. 

 The admittedly fanciful picture drawn by Dr. Nichols of a sup- 

 posed post-glacial tundra vegetation on Long Islandt has practically 

 nothing to support it. While it is true the three plants mentioned 

 in paragraph 39 suggest a glacial origin, they may well have 

 followed a regular migration path via Staten Island. The fact 

 that Linnaea, Pyrola chlorantha, Caltha flabcllifolia and Campanula 

 rotundifolia are not now found on Staten Island means nothing, 

 as they might readily have traversed the island long ago, and 

 have been destroyed by conditions that are now unfavorable. 



42. If, as seems probable, Long Island was without vegetative 

 covering just after the final recession of the ice, then all of the 

 New Jersey flora now found on Long Island must have had a post- 

 glacial origin. The distribution of Pinus echinata, and the red 



* Stone, W. Loc. cit. 73. 



t Long Island was probably not covered wholly by glacial drift, but the sandy plain 

 south of the moraine received considerable overwash material, now mixed with the 

 underlying Tertiary sand and gravel. 



| Nichols, G. E. The vegetation of Connecticut. Torreya 13: 92-93. 1913. 



