EXLANATION OF PLATE XIX. 



[Figures natural size, except when otherwise noted.] 



Fig. a, branch boariug male innorescence; h, young fascicle of lea^-es (siiriiig); c, (1, forms of mature leaves; 

 traosverse section of leaf buuiUe sUowiug structural characters of the leaf (as explained for Pinus echinata)/,, 

 magnified 20 diameters. 

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