PLATE LXXXI. 



PAGE 



Figs. 1-le. PopuLus potomacensis Ward 458 



1-lc. Mt. Vernon, Virginia (after Ward). 



Id, le. WTiite House Bluff, Virginia (after Ward). 



Fig. 2. PopuLOPHYLLUM MiNUTUM Ward 460 



Near Wellhams, Maryland, 



Figs. 3-6. PopuLOPHYiXTJM EENiroEME Fontaine 461 



Aquia Creek Cut of R. F. & P. R. R., Virginia. 



580 



